Some advice please! :)

Hi everyone, just wondering if anybody could give me some advice. TTC my second since August. I'm currently 5 days late. Did a test the day I was due but it was negative and then did another yesterday and still negative. It is very unusual for me to be late. I've had nausea the last three mornings and also around the same time each night (about 10pm). I've had cramps that feel like my period might be coming on and off for the past week but no sign of it. No idea what's going on!! Just want something to happen because no period and two negative tests is really odd!! Anyone have any idea what could be happening?! Thanks x