Late period!??!

Soo a few months ago i had a miscarriage. I was 7 weeks when i lost the baby, it was due March 27th 2015.  My period started back up an in october it was 7 days late an came the next day an this Nov comes around an i started my cycle date from the date my last period started an i figured 28days would be Nov 6th. Well here we are 9 days late an still nothing. 2 days ago b4 bed i wiped an there was a streak of blood so i put on a pad n went to bed, i woke up next AM expecting to see my period an nope! Not one drop. I took a pregnancy test today an it was a negative result( big relief) but im still worried. Idk if it has something to do with the fact i really havent had an "on time" period since my miscarriage or what. Im really stressing out about it..