Can't even enjoy this pregnancy

I feel like I'm losing my mind!!! Doctor says I'm going to miscarry two days ago. Since then I haven't slept at all. This month I was supposed to have my baby that passed in March of this year, so I found out I was pregnant on Set. 17th I was estatic. All until I got my Hcg results back, first ones were 50.7, 337, 443, 466 and he decided to do another one because I insisted and I'm still pregnant as of now. He originally wanted to wait to see if I miscarry in 10 days, and if I didn't he wanted to do a D&C. Well I called the office this morning and I told them how I felt about all of this. I feel like we should test again and follow through with the original plan, and that was with the scheduled ultrasound on Tuesday. So they agreed, well here I have been up for days reading about this stuff and being dehydrated could cause Hcg numbers to go all out of wack. Your thoughts and experiences or welcomed I really need closure and answers. This waiting game is killing me, I almost want to go to the ER and get an U/S to find out where I stand. The other thing I wanted to say is, we don't know my due date, because I don't remember when I started my cycle because it's been all over the place and I just gave up on ttc and surprise I got pregnant.