What Causes Bumps In Vaginal Wall?

I am trying to get pregnant so I check my cervical mucus & cervical position often. A couple of weeks ago I noticed 3 very small, hard bumps under the skin on my vaginal wall. They are basically in the wall if you would insert your finger and curl it to the side. They don't hurt & they haven't gotten any larger. I was just curious if they could be some kind of cyst. Thanks.