Irregular bleeding.

Gemma

So I was due on my period on 31st. I had spotting for a few days on and off leading up to my period. Came on on the 31st and only had a period for 3 days. (Usually it's 5) then I stopped and now started bleeding again this morning.Anyone had this happen to you? Trying to work out why. Maybe stress or can taking folic acid be the cause? I've never had this before.