Boobs very sore

So I’m on nexplanon for about 6 months and I had a period for a while but it has stopped in the last 2ish months. I am sexually active like a lot with my bf and we dose finish inside and my boobs have been very very sinsitive the past couple weeks and I’m hoping I’m not pregnant but I don’t know, if it’s him being to harsh on my bittys or I’m pregnant, should I take a test to be positive I’m not or am or could it just be hormonal thing and I have been very emotional the past week like crying over wrong food or just simple things or grades. It could also be stress cuz my exams are in 3 days but I have no clue so any advice would be cool