2 day period or withdrawal bleed

Avril
Hi all 
So long story short af was due on the 4th of this month (November) but didn't come until 6th and it was only a 2 day bleed? I have recently come off the pill mayb 2 weeks before this happened some multiple tests due to nausea cramps dizziness and backache all negative :/ 
Could this of been my period or withdrawal bleed and could anyone tell me when I'm likely to ovulate if it was either 
Thanks girls lots of love xxxx