I feel like I'm falling apart

So my period is late, going on about 5 days now, When I thought I was in my 2 week window I started to get massive spots on my jaw on the right hand side (Not unusual but usually happens when I'm really stressed) I know this can be caused by oestrogen, and since the day I thought my period would start I've been getting painful mouth ulcers too. Am I just really run down? Did I ovulate later than I thought? Or are my hormones just all over the place? I've taken tests and they have been negative. Please help!!