Just another update...?

So, I posted it earlier today that I got a BFP earlier this afternoon with a Clear Blue hpt. Well, I just took another hpt, this time First Response...and there it was, 2 very bold, pink lines!! I guess I really am pregnant. I have my appointment with my doctor tomorrow and hopefully they will confirm it. I have a bit of a sore throat, headache, sore legs and lower back, a bit of a stuffy nose...but no sore yet. I wish baby dust to all you ttc and this is my 1st so if anyone could fill me in on what to expect in the coming weeks and what the chances of a miscarriage are? Or better yet, how can I prevent something from happening to the baby?