Excessive bleeding /extremely heavy flow

So this period has been anything but normal for me...never had this heavy of bleeding and I may be making a trip to the ER if it doesn't slow down...I started my period on Tuesday...so I am at CD 3 right now...I have been bleeding so heavy that I am changing my tampons every hour on the hour and half the time I'm already starting to leak through....I leaked through twice last night and everytime I pull the tampon, blood just comes out...the bleeding is so excessive that it's got me really weak, headache, sleepin most of the day and the cramping is harsh....I know that it can very much so just be an extremely heavy cycle...but does any of this sound normal to you guys? Or anyone ever experienced this and if so, what did you do and what was the outcome ?