Hi! Sometimes a few on my plants do that too. If they start trying to fruit when the plants are too small, I think the peppers come out short and stubby. Try pinching the flowers off the smaller plants and let the plant itself get bigger and more established before allowing it to fruit, and I think you may get longer peppers. They will turn red once they are done getting bigger, so if they're red they won't get any larger. Let me know how it goes!