What is the most likely culprit?

I've been really sore and sensitive in the pubic area for about a week now (I'm a girl) and I've tried googling things but google tends to jump to the worst possible case. It doesn't actually hurt to touch it but it does hurt when I walk sometimes and if I wear tight shorts. I did have some thick white discharge befoew the pain occurred but I wouldn't describe it as "chunky" like they say for a yeast infection. I would say it was slightly unusual though so I kept and eye on it and it went away in about 2 or 3 days. I'm on birth control and I was sexually active with my boyfriend about 9 months ago. We're still together and we were both virgins before. I do have a slightly swollen lymph node on one side which is I assume why I always get STDs when I try to figure out what I have. I know it's not IMPOSSIBLE but it's very unlikely considering the circumstances. Could this be a yeast infection? I know that my pill warns that I'm more likely to get those. I plan on going to a doctor as soon as I can but I'm a worrier and I prefer to have other opinions.