This to me sounds like DOMS.
Particulary if you haven't done this type of resistence training before and your form was good. Also the soreness caused by DOMS is a dull, aching pain in the affected muscle.
As the article says:
The pain is felt only when the muscle is stretched, contracted or put under pressure, not when it is at rest.
I find that if I haven't exercised in a while and then I hit the gym hard the effect of DOMS is worse after the first few sessions. The soreness usually leaves after approx 72 hours. But with regular exercise the effect of DOMS gets less and less (but never really goes away).
To treat DOMS you can try to increase the bloodflow to the affected muscle by perhaps doing a as low-intensity workout, massage, hot baths, or a sauna visit.
If however the pain isn't as described as above and is present at rest then you may have injured yourself and may need to rest from training and perhaps consult a doctor.