Missed period/ spotting

Larria
Hey ladies, 
So I was supposed to start my cycle on 7/28 and today is 8/1 and no cycle. One the morning of 7/28 there was a drop of blood when I wiped and nothing else happened until I wiped this morning 8/1 and there was a little clear stretchy discharge with little hints of blood. I'm sooooscared to take a pregnancy test I don't want to get my hopes up. Also this is month 4 of being on Metformin and since I have started my cycles have been like clockwork every 26 days and now this. Has anyone had this happen to them? Help!!!!