ib bleeding ?

Thursday I was already 2 days late for my period and nervous. By afternoon Thursday I had spotted. It was red and I thought my period had come. I put on a pad and nothing. Friday I bled very lightly. Probably wouldn’t have filled one pad all day. Saturday same thing super light only needed to used panty liners. By the end of the day Saturday I wasn’t bleeding. And now today I wiped this morning and the blood is now brown. This is nothing like my normal period. My normal period is 4-5 days sometimes 6 depending on how well I’ve been eating and drinking water and usually pretty heavy the first few days. Do you all think it’s just a one off weird period ? Or IB ? I should add I’ve been extremely tired , hungry , can smell something strange from mile away , crazy mood swings. I don’t get nauseous but I also didn’t get nauseous with my first born.