College Relationship

I started my freshman year of college this year fall 2019. before I actually got there during the summer, this guy who’s a sophomore at my college started to pursue me thru Instagram. I didn’t pay him any mind at first but as time went on he was showing me the ropes & answering questions I had before I got to school. We met on move in day & he was the sweetest thing ever, we would spend time together & it was just great, told each other we loved each other, spent the nights together and all . Anyways, In October I went thru his phone & found out he was a liar, he was having sex with so many other females more than 5 including his ex who doesn’t even goes to our school she came up there, girls was buying him things, I honestly couldn’t even keep up. My first real heartbreak, I couldn’t eat for days I was just depressed & sad. Since then we haven’t been the same but that’s another story. My concern now here is I’ve noticed like this weird odor from my vagina like a real fishy smell, I’ve never smelled like that until now. At first I was confused, but as I started to think we had sex unprotected & he was having sex with so many other ppl, could that be the reason why? I got tested & they all back negative but the smell is still here. My hygiene is great I take a shower everyday & clean myself properly but after a couple hours the smell is back with a white discharge. I got yeast infection cream and it was good but came back after a couple of days. I’m 18 & never been to a GYN but now I’m considering it, what could be the issue??