Currently on bactrim (sulfamethoxazole and trimethoprim) and cephalexin for a skin infection. added advil for pain but it still hurts too much. anything stronger i can take?

Assess for abscess: Though other pain meds are available, if you just started the regimen, then you may experiencing increasing pain the day after- it's called the "antibiotic effect". This pain will decrease over the course of treatment. Otherwise, if the infected skin is warm, red, very tender, swollen and boggy/fluctuant, then it may be an abscess- if so, see your prescribing doctor for re-evaluation.