Bee in my tomato plants.?

i have four tomato plants each in a small plant pot. i was planning on repotting them today into some bigger tubs but i have noticed that in the soil of one of my plants, there is a small hole and every now and again i see a bee, not a wasp or a bumble bee, go into the little burrow. i'm worried that if i try to repot the plant i will annoy it and it will sting me. what should i do?????