Help me anyone

So November 9th my boyfriend and I had unprotected sex. I missed my period at the end of November but did spot for a day. December 12th I took a pregnancy test late evening after working I had to pee and held it for a good hour/ hour and half. I also hadn’t drank much that day. That test was positive. But then 5 Then the next morning I got up early and peed on another test. It said negative. They were the clearblue digital results tests. I had bled the 21-23 very heavily than usual and I thought maybe I got my period. Then 4 days ago I got a very bad UTI. I have been having all the symptoms of pregnancy right now. My hips, butt and thighs have gotten bigger. My boobs and nipples have gotten bigger. And then also I have been having this horrid nausea. We thought it was the antibiotics but then my sister stopped and asked me if I had a chance to be pregnant. I said no Because nobody in my family knew I had sex or was sexual active because it was my first time in the first place. I told her no it wasn’t possible but then I stopped and asked myself Yanno I have noticed a lot of sudden changes in my body and mood. I take a birth control but I only take it until I’m supposed to have the week of my period. But the last 5 days I haven’t taken it and usual when I go off of it I bleed within the first day of being off of it. I haven’t bled at all. Not a drop not even any spotting. I’m worried and can’t tell anyone unless I was to know an answer on this. I can’t drive myself to get a test and my boyfriend keeps thinking I’m making everything up cause he is saying he didn’t finish in me but I explained to him that him finishing in me is the only way to get me pregnant that there was such thing as Pre cum too. I am 18 and he is 17.