I found a lump on the side of my vagina it the same color as my skin and hurts when I touch it and it can't be a std I have been with the same man for over 5 years and 99.9% sure that he has not cheated... what could it be..

I say this your 99.9% sure but if it was me I would go to a doctor and have them look at it. Then you and the man need to be tested STDS. It's the best thing to do.