Confused re the big O - please help

Lisa • Married 5 years to a wonderful man. Son born 26 Jan 15. Expecting another boy in Nov 16 X
Hi ladies,
​After a delayed O this month I'm a bit confused....
​I had positive OPKs yesterday, this morning - they are negative but bbt dropped by -0.3c this morning so I guess I haven't ovulated yet - is that right?
​Thanks
​Kathryn