Here are a couple of possibilities. I've never seen the fall armyworm, but that would be my guess. I've seen plenty of corn earworms and they are not that darkly marked.
Corn earworm - Early instars - cream colored or yellowish-green with few markings; later instars - green, reddish, or brown with pale longitudinal stripes and scattered black spots; moderately hairy; up to 44 mm long; 3 pairs of legs, 5 pairs of prolegs; leaves holes in peppers
Fall armyworm - Green, brown, or black caterpillar with black stripe down each side and yellowish-gray stripe down back; body up to 40 mm long; 3 pairs of legs near head and 5 pairs of prolegs; head capsule with pale, but distinct inverted Y; eats leaves and gouges fruit
