Is this normal?

So I officially started my period 3 Weeks ago. Everything was fine and normal. It stopped after a week, like it should. But then, two weeks later I started again and it only lasted for a day and then it was gone. Then last week I started again for a day and it was gone. Except this time it was really clotted and clumpy. Then today, I woke up and it is there again. This time it is also extremely clotted with big clumps. Is something wrong? P.S. I am 14 and haven't really started having regular periods yet.