Spotting to bleeding

i have had 3 MCs and have been very closely monitored, I am 9 weeks and baby has grown/HB risen each week. Had an u/s Monday and today I was spotting and just saw two red drops. I freaked out and am seeing my doctor tomorrow. I am so sad/scared that this could be the start of #4. The baby was fine two days ago, how can this be happening? Any positive vibes/stories to share?