Could I be pregnant?

Hi! We had sex Jan 7th and Jan 10th. I BELIEVE I ovulated Jan 11th so I think it was all in my fertile window. From Jan 17th or so up until now I’ve been constipated, sensitive to foods (I almost threw up after a bite of shrimp which is one of my favorite foods), I’ve been super weepy and emotional and perhaps the biggest thing, my breasts are simply different. Even my fiancé noticed. They are bigger, firmer, heavier, sensitive, my areoles seem puffier and my nipples are definitely bigger. The veins in my boobs even seem more visible. But my real question is, I started my “period” 3 days early on Jan 21 when it was supposed to start today, the 25th. I’ve never been early or late in my life. I thought it was my period because I was bleeding pretty heavily like my period and having bad cramps the first day. But now I’m not sure because I only bled for 2 days and then stopped. I’ve always bled a good amount for at least 3.5-4 days and then light spotting the 5th day. Is it possible that was implantation bleeding even if it was heavier than it should have been? Should I take a test?