I just went through this and I can tell you how frustrating and heartbreaking it is. I'm not going to tell you to hope for the best cuz it doesn't work that way. It sounds like it's most likely a chemical. Just pray that your beta goes down to normal by Monday and you can go off your meds and start over. I know that's not what you want to hear right now, but it's the truth.
Most people have much better success with FET's anyway.
Thanks everyone. I don't know what I'd do without all of you. My DH has no clue what's going on- he doesn't seem to be grasping anything past 'but it's positive- you're pregnant' I managed to cry myself to sleep in his arms and sleep for a while but now I'm awake again - and I feel just as bad. My head is about to explode and I keep running into the bathroom b/c I feel like I'm going to get sick...... I really hate this. I hope that tomorrow is a little brighter... I am usually one that can find hope in things, but today I just can't. Monday seems like a lifetime away....... Thank you again.
. I have to agree with Gerty and say that it sounds like a chemical. Try to stay positive for a FET.
I'm sad and angry for you! You and your DH are in my thoughts 
