honestly, the tests helped me a ton! i got the cheap ones from target (the strips) and then when i got a +, i used a digital one to confirm.
my dates were off, too. i honestly don't think i wouuld have caught my surge if i hadn't been testing. one month i tested + on CD 13, one onth i tested + on CD 16. our bodies are weird!
ps - i live in chicago now, but was born and raised 30 years in san diego!! love cali