so after having my daughter my period would always come on time I don't use the <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period tracker</a> I always forget too mark my period and when we had sex ugh I'm now 3 days late I took a test and it was negative should I wait a week and retest? I do have slight cramps and my lower backs been killing me I can't sleep on my stomach it hurts and I've been tired so much I need some advice please