Still bleeding

I am scared to death right now. Yesterday just as I thought the bleeding was completely stopping, at 4:30 this morning I got up to pee, and when I wiped, there was bright red blood and lots of it.  I contemplated going to the ER but decided to lay back down to see if it would subside. At 7:30 am up until now, it has gone back to dark brown but there's a lot and even kinda chunky (sorry TMI).  I also have some light cramping, but more than normal.  I called my Dr. and she said this still might be due to my vaginal u/s on Tuesday and the fact that I just started lovenox  (blood thinners) injections.  She told me to stay home, put my feet up and not do anything this weekend.  She said if I start any bad cramping and/or alot of bright red blood again to call her and she would send me to the ER.  She said she feels positive that Tuesday's u/s revealed a strong heartbeat (150 beats p/m) and everything looked good and that she really thinks the extra bleeding is due to the lovenox.  So now it's just a waiting game.  I'm utterly and completely scared to death.  I just don't have a good feeling about this.  I just don't think I can go through another miscarriage again.  I know I shouldn't stress but I'm so upset right now.  Why does this have to happen to me?  On top of it, one of my oldest and closest friends just came in for a visit with their three year old.  I haven't seen them in over a year and we were supposed to go to the museums and tour Chicago today.  Well they're there with my bf without me.  I know they understand but this weekend just sucks!  I wish I didn't sound so pathetic but why can't things just go good for us?