Congratulations, mountainboo! Just go with it, your body will be taking care of everything so you just take care of yourself. You could always do another test in a few weeks if it'd put your mind at rest? As things progress, the midwife will be able to date things more accurately - you can even ask for an early scan to get a spot-on date if there IS a question mark over your lovely bump. They all NEED to know just as much as you WANT to know!!
Get plenty of rest, and eat as healthily as you can. I'd do it all again in a heartbeat - it's an amazing process, so take time to enjoy every last second, you lucky, lucky girl! xxxx