I Have Had A Lump On My Upper Labia Majora

I have had a lump on my upper labia majora for a few months now, at first I thought it was an ingrown hair and ignored it but its not getting better.I also have swollen lymoh nodes I'm my groin, I could feel 2 of them, now I discovered another one. I've been to the doctor twice, he gave me antibiotics but it didn't help.I don't wanna go back, he just says I worry to much and sends me home! I'm 19 years old. Should I be concerned about cancer? Should I try a different doctor?