Ivf - scared of possible miscarriage

Hei there - I'm on my first icsi cycle, now 16dpo. I had very severe cramping since saturday. So they did some early blood testing on monday, which was repeated yesterday. Whilst they said that I registered pregnant, they also said my numbers are way too low and I gonna most likley to miscarry. 13dpo I had a beta of twenty, 15 dpo a beta of 40. They put me back on progestan and I gonna have another test on 18dpo saturday. I'm going out of my mind here. I'm ok with it not working since this is the first cycle, but the not knowing kills me, especially the thought of it that it may be ectopic. Did someone had something similar?