need advice, has anyone gone though this? help please

Lauren
So I was 4 days late for AF! And was getting excited! Normally always on track! And haven't been late for over a year since I finally got AF on track! Then the dreaded beast arrived! (Monday)
But this one hasn't been like my normal periods! It was extremely heavy and a lot of strange clots! I've been extremely and painfully bloated and feeling extremely sick (haven't been sick) and headaches, I've had some extreme cramps that have caused me to curl up in a ball and my presricbe meds wasn't helping (they are strong)!! I've been feeling more sluggish and been having to change every hour to 1 1/2! Even waking up at night! 
Then all of a sudden yesterday (3 days days later) I've gone extremely light to practically nothing! Which is strange also as always on for 7 days!! Still painfully bloated and feeling extremely sick and getting headache!!
Has anyone else experienced this? 
I took a test which came back negative (before AF started and while I was still late)
I've told my symptoms to a close friend who says it sounds like a miscarriage! So I'm worried now!!
Should I go doctors? I'm worried I'm just panicking more then I should be! Or it's it just nasty AF!!
Help please and thanks for any advice!