help!!

Hello! I missed my period for three months in a row. I think this was because I gained weight and there was an irregular amount of hormones in my system. However I got my period yesterday. I have never had a period like this before. The cramps are close to unbearable and I have been bleeding soooo much. I have never bled this much. I filled an entire tampon in less than 40 mins. Just wondering, is this normal? Does it have something to do with my period being MIA for three months? Thank you!!