hmmm, I had some beloved geraniums that I took cuttings from, and the tips fell over same as your peas. I just happened to pick up one of the fallen tips, and there rolled up in a tiny piece of leaf was.....a worm.

Next time you have something drop, take it and very gently examine the leaf. Once I found out what it was, I used
Sevin dust, but of course my plants are not meant to be eaten, and they are in pots.