I’m new to ovulation tests

So my cycles are between 35-50 days long... we’ve been tcc for over a year and I just went to the dr to get fertility tests done but have to wait until my next cycle starts to start tests... so I got some ovulation tests to at least keep me busy while I’m waiting to get medical help. Well I would take them every couple days and never got a surge however last night on cycle day 30 I got a strong line. Could that still be ovulation even though it’s late in my cycle? Or just aunt flow coming soon. I read it can be positive before your period comes too and now I’m just lost did I ovulate or not? 😞