Has this happened to any 1 else

I had my period on the 16th of December for 4 days then again on the 3rd of January for 7 days and I came on my period again today I know my body and I've never had 3 periods in just over a month befor it's starting to freak me out a bit ......has this happened to any 1 else what could be the cause of this all & any advice would be great ladies