Tissue on outside of vaginal opening

i am very young (17). I have never been to the gynocoligist, but I have had sex, with my long term boyfriend of 4 years, he is my first, and i was his first. Anyway, i sometimes get thick discharge, like very thick it smells, and ive started getting it maybe about a year ago? but every once and awhile i get it, not constant. also, i get a lot of urinary track infections, mostly only after i have sex. sometimes i think its just from the condoms i use? I also get a sharp pain it feels like a gas pain but on my left lower pelvic area. and about the tissue, ive noticed the i have on the outside of like the opening of my vagina, where you would have intercourse, i have these, weird whitish kind of like blobs of tissue? like and when i touch it its a little sensitive but they have been there for awhile.. i cant really explain it better than that i dont no what there are, or if there dangerous in any way? but, is there anything wrong? am i okay?