So I was meant to start my period on the 20th of this month but I didn't start bleeding. Then on the night of the 21st my dh and I had sex and when I wiped afterwards I saw very pinkish blood and only on the tissue. Thinking my period was about to start I put a pad on but the next morning nothing. Roll on thr afternoon I noticed my pad had this rusty coloured blood but it's not the heavy flow I usually expect on my period. I've just been to the bathroom and when I wiped it looks more reddish now but still my flow isn't getting heavy.
I've had back pain, cramping, sore breasts on and off and noticed a few bumps on my nipples which suddenly disappeared as I was changing my clothes in the morning. I've been bloated and gassy and felt very mild nausea and my current body temperature is 36.3 and I feel like I'm freezing and then suddenly I feel hot and sweaty. Smells have been strong but not gag-worthy. Just re-examined my nipples and the left one has bumps but the right is bump free.
What's wrong with me? 
Have uploaded pics of my pad and the tissues when I wiped just now. I apologize for the super graphics. Please ignore them if they make you feel squeamish.