16 year old needs advice

Hi. I'm 16 years old and I made a stupid decision. I always have sex with my boyfriend with condoms and June 18 we decided not to use it for the first time and he ended up cumming in me. My last period was June 2 but my period are irregular for my age. Idk if late or not. I took a test today and it said negative but no sign of period .. Just cramps on my sides and sometimes cramps it feels like it's around my ovary. Idk if it's me peeing a lot .. I feel like I'm peeing a lot or my mind is playing tricks on me. I heard you can take a "bbt and if it's high you're pregnant"" whatever bullshit and I took it it was 99.1 I'm worried