What is going on ?

Ok so I have missed my period by more then three weeks and days before that I had some strange spotting what I thought to be implantation bleeding because it was directly six days after I had intercourse. Now I have missed the start of my next period by three days and I have yet to have a positive pregnancy test. I have CLEAR not white, mucus-like discharge but it doesn’t smell or anything.. I’m not sure what could be going on.? Any help?