I get this bump on my inner thigh after taking a shower?!

I've noticed in the last month every few showers I get this bump on my inner thigh. It looks just like a mosquito bite, it's the color of my skin, the skin around it is usually flushed as in red, and it's about the size of a drop of honey. I don't think it's a insect bite because it keeps coming back. I'll get out the shower, dry off, lotion up, get dress, and about ten minutes later it's gone. Well, it swells down and during the week I can sort of see a tiny blemish on my thigh where the bump keeps popping up. What can this be? Oh, and it doesn't necessarily itch.

I'm 16, and I'm a virgin if that helps. I've never had any nude physical contact with a guy or even kissed one. I'm too afraid I'll get something, my friends say I'm paranoid. So what do you think? Please help.

Thanks in advance.