Thanks purdey I've only ever tested twice over the last 2 years. The first was a 33 day cycle, longest I'd had. Tested at 8am, af arrived about 10am 
The 2nd time I was so convinced I was preg. I had nausea and heart burn for days. Af was 5 days later than I thought it would be due to when I thought I ovd. I left it so long to test as I wanted to wait until after 33 days as longest ever cycle. Again I tested bfn first thing and then af arrived 2pm. Never tested again. Too much for me, plus got crap sperm results back month after that so lost all the hope I used to have each month.
Sorry for me post x