Is this normal or not, also I go after I leave work at 5pm and I feel really hungry even after dinner, but this is only when I go to the gym.
Yes, it's normal to want to eat stupendous quantities of food after a hard workout.
Sometimes I find it's hard to eat enough food to satisfy my hunger after a really tough workout. This is particularly true, I found, when eating lots of greens and beans and other low-density, low-calorie foods. I find that a post-workout meal best defeats hunger by including nutritionally dense foods like meat, eggs, milk, fruit, potatoes, and sweet potatoes, all with plenty of butter and oil. If you're working hard and not trying to restrict food intake, then listen to your body and eat plenty.
If I still feel hungry after dinner, have seconds, or wait an hour and snack on something dense like canned fish, a milk-and-fruit shake, peanut butter, or just leftovers.
One reason for extreme hunger could be that you are doing long hours of cardiovascular exercises. For instance, running on the elliptical for long periods might really drain you of energy so much that you end up over-consuming food afterward. It's not really healthy in any way either. One way to avoid that (and get stronger and leaner in less time) could be to limit such cardio-intense long workouts to 1-2 times a week, and to do shorter, more intense HIIT style training for the remaining couple times in the week. Metabolic conditioning workouts are all the rage these days - they save time, are more effective, and won't leave you so famished as a side effect either.
Of course my answer assumes a lot of things about the way you are currently working out.