What Causes Heavy Spotting Between Periods?

I had my period 2 weeks ago and it last for about 3 day. 2 days go I whiped and saw a little bit of blood on the toliet paper, no big deal I figured I was just spotting. But I began to bleed more and more and now it is as heavy as a normal period yet the blood is bright red and doesnt have the smell of period blood. Is this a big problem?