So confused

So we have been ttc since my 2nd Mc in July. My period was suppose to start yesterday (Friday), it didn't come. Glow moved my period to tomorrow (Sunday). A couple hours ago I started getting a really sharp pain on my left side towards my back. I don't want to test until tomorrow morning, has anything like this happen to anyone else? I have never had this kind of pain and idk if it's from ttc/pregnancy or what but it hurts 😞