What Causes Heavy Bleeding With Blood Clots?

I just started my period and yesterday I had a heavy flow with jelly like clots almost like discharge my period was a day late its a bright yet dark red and I dont have a foul smell or any other colors coming out of me… this is the first time it has happened and its now light on day two I have had no cramps or anything like I normally do the only symptom iv had is a lil fatigue… .is this normal? What can be causing this?