[I copy-pasted this question, without any change, from Martial Arts SE where it was closed as off-topic]
I don't know what to do. I'm desperate. I do pushups regularly for almost three years but not only haven't I managed to reach some decent increase pace (I hope you understand what I mean by my clumsy English; "increase pace" sounds a bit off to my ear but I don't know how to say it otherwise), I also every so often see the number of my repetitions fall by 1, 2 or even 3 with no apparent reason at all. Last time I did this type of pushups (it was 4 days ago; two days ago I did wide pushups), I did 32 repetitions, the same as in late December (and last month I managed to do 33). Today, without any evident reason, I couldn't straighten my arms after just 30 pushups. In these three years, I tried everything I could think of:
I experimented with the number of days between similar exercises (initially, I did pushups every day, then every two days, then every four days, then every three days, now I got back to a four-day cycle, i.e. no pushups (abs+squats, instead) — regular pushups — no pushups (again, instead, abs+squats but different) — wide pushups, and then all over again);
I experimented with the number of sets (initially, it was just one set, then two sets, then two sets of one type and two sets of another type, then many low-rep sets, now I'm back at two sets of the same type);
as already mentioned, I experimented with different types of pushups (initially, it was just regular-width pushups, then I mixed in narrow/diamond pushups, then found out that diamond pushups target the same triceps so I replaced them with wide pushups that target pecs);
I don't eat fish; maybe, it has something to do with iodine deficiency, I thought? (I didn't google it, though) I started popping iodine pills, no difference;
every time the number of repetitions drops, I started to take three days off of any pushups (it's my most recent experiment); it, actually, proved somewhat effective: after such a break, the number of repetitions slightly increases (usually, by one); but guess what? I took a three-day no-pushup break just a few days ago (two days ago I did, as I said, wide pushups, two days before that, like today, I did regular pushups, three days straight ahead of that I did no pushups).
I genuinely don't understand why sport punishes, instead of awarding me for my daily (with rare exceptions) efforts. Back in school (I'm 23 now), I could do 50 pushups (though, not easily and not very well performed). Since the start of middle school (if you consider the fifth grade middle school, probably not), I regularly practiced one sport or the other (unfortunately, never succeeded), but never have I exercised as intensely and regularly as I do now and I get almost nothing in return. It's not supposed to happen. Such illogical things happen only in dreams when you realize the whole weirdness only after you wake up. Only I caught on to this irregularity while staying inside the dream and that realization doesn't bring me back to "the real world" where no person (even a person like me who always struggled with sports) exercises essentially every day for three years and only manages to increase the number of their pushups from 10 to 32. It never happens and never happened. I hoped to lift myself from my depressive state with the help of these home exercises but instead, it only makes my psychological state worse. I hoped to prove to myself that I am able to achieve results at all. The only thing I proved to myself at the cost of all that time, sweat, and pain is that I'm some defective model to whom normal rules don't apply and can't achieve anything. I hope to find some advice here. I already unsuccessfully tried to find help on Quora and on Russian Quora (Russia's Quora-like website).
I posted it here because physical exercises are only part of my 60-70 min. daily training which also includes stretching (btw, no splits still) and some karate technique retained in my memory from my school days when I went to a dojo three days a week for ab. 4 years (guess whether it was fruitful); I hope to restart my lessons someday with a good sensei who would care at least a little bit about my success — once I have money. There's a marginal chance that that circumstance is somehow related to my problem (even when I don't do pushups or pullups, I still, to some extent, engage my muscles while doing all those blocks and punches — maybe, I never let my arm muscles rest properly?). Anyway, I don't know where else to go, I don't know much Q&A websites (I found this one only recently).
P.S.: Even if my question doesn't fit this forum and violates some rule or something, please refrain from deleting it, at least not before redirecting me to some other place (yes, you don't have to do it, that's my request). Lastly, there's no scintilla of trolling, joking, sarcasm or anything in my text, in case you find it too strange to be real, I'm dead serious