Late ovulation and short cycles, when can I test?

[JessJR23]

Hi all, I am really hoping I might be pregnant this month after trying for 6 months to conceive a second baby (my first is 28 months now). My question is when can I test? I am due on tomorrow BUT I have used ovulation kits which tell my I ovulate on day 17 of a 24 day cycle. So on my period 'due date' I could only be 8 days pregnant. Would a test even show that early? I have been doing the mad pregnancy testing for 6 months (and worrying endlessless that my ceasarean may have caused scarring) and am trying not to set myself up for a fall so any advice would be appreciated.