Question?!

How late can one be with their period and still get a negative test? Going on day 4 no AF... last mo or so AF was 4 days late..this time feels different but when should I test again? My boobs hurt so bad, cervix high closed n firm...cm is clear/watery, I'll get cramps on and off..with my first didn't get s positive til I was 6/7wks along...