STD?!

I've only been sexually active with one person my whole life. He never had any STD and I've never had an STD. I have a son, which means I've been tested for stds when I was pregnant and when I gave birth. Today when I was showering I felt 3 bumps around my labia, but they also near my Butt (TMI) I'm so sorry. They aren't in the same area, two are on one side and one is on the other side. Two of them are white and look like pimples, one of them is red. They look like ingrown hairs but I have no idea! They don't hurt and I've never noticed them
until now! Could this be an STD? I'm 22 and I've only had sex with him, and me and him both got tested and we have nothing. I already have a lot of medical issues and I'm scared to death. I feel disgusting.