Chemical pregnancy- ovulating right after?

I tested positive last Tuesday then started to bleed Thursday 26th - Monday 30th... I took another test on the 4th and it was positive still... Took another on today the 7th and it was much fainter then took a clear blue digital later on and it said not pregnant.. 
Is it chemical? 
Also I'm having a lot of CM and would I be ovulating already if that was my "period"? 
First picture was on the 4th second was today