Period

Ok so according to eve my period was late by 5 days. It was supposed to start last week. I was away for home due to state convention for FFA. I haven't had sex in awhile. When I got home from being on the van for 5 hours and noticed I started my period. When I woke up I used the bathroom and it was like a crime scene in the toilet. I started it Friday night. Saturday and yesterday were normal flows. Normally my period lasts five days. Today my period blood was brown. Then turned red again. Then after I changed my tampon the tampon was brown. Like I seriously want to know what's going on I'm freaking out!