The pill and pregnancy?????????????????????…

am on marviol and take it at the same time each day.. I had almost 3 wks ago this friday.. ive bn under a lot of stress. I have a lot of pain in my upper tummy just by my bone.. and feel sickly.. i just did a test this morning which would make it almost 3 wks since .. How accurate wld that be. (i had at end of pill free week but did have a tummy bug then so don't know if it effected the pill) could all this stress just be making me feel ill