confused

I'm really confused right now, my period every month is the exact same. Sometimes it's a day or two later than planned but it is ALWAYS only 4 days long. Ever since I started at the age of like 14 I believe. First two days are really heavy then the third day is moderate and the fourth is very light spotting. Also I have cramps my first 2 days so bad I throw up sometimes, then after that the cramping is pretty much subsided. Well here I am 2 days after my period should have ended, and now I'm cramping really bad and bleeding heavy. Almost like I just started another period. Is this normal.? Has never happened to me before and I'm 22 years old.