My Weird Period

I have been expecting my period for 3 days, and it only just came now. But that's the weird cause I have had suuuuper late periods in the past, but this was weird. I've been having cramps for the past past 3 days, my boobs are sore, but there hasn't been any bleeding. Until just now. Now I'm used to a very heavy and long period. I'm 19 and this is the first time I've ever experienced this. Not only is there barely any blood, but it's a different color then normal. Has anyone else experienced this, or no what might be the cause???