Sharp pains in lower abdomen

We have been TTC. My period was due today.. since two days I have sharp pains in my lower abdomen. since two days I have a slight brown discharge. Never had it before.. Nausea and vomiting specially in the evening and feeling too dizzy all the time.Today I am due for my period but havent got it yet. But sometimes i have these sharp pains that make me sit down holding pelvic area, specially when i bend down or move around quickly.Will test tomorrow and let you know but is it normal to have such sharp pains.