What Does Bump On Outer Lips Of Vagina Indicate?

Hi. I saw a bump on the outer lips of my vagina, it looked like a hair bump so I put some heat on it until it came to a head and popped it. It didn't come back so I thought nothing of it. Then a week later I got a smaller bump on the other side. It doesn't hurt until I bother it. It has a white center and a little red on the outside. I have no burning when I urinate, there is no funny smell and I have no discharge. The very last time I was sexually active was March 22. Could this be another hair bump or something more serious?