Confused! Could I be pregnant?

I'm like clockwork. Every 24 days I start my period and even between certain times of the day!! So I'm 3 days late and today I noticed what I thought was blood but wasn't the normal color, it was more of a pink instead of red red and a little brown. It's only there when I wipe. I've been sooo extremely tired this past week when I haven't been doing anything out of the ordinary. I get lightheaded when I stand up, feel sick to my stomach after I eat, have been getting headaches which I normally don't. Craving chocolate (I don't eat chocolate!) and have been drinking water like a fish... yesterday I just had a strong strong feeling that I was pregnant... I'm about to run to the store for a test but have heard they aren't the most accurate! Can't get into my doctor for two weeks!! HELP!!!