I think I'm having a miscarriage

Hi this is my second baby my daughter is about to be 2 in July I finally got pregnant everything was great until yesterday I turn five weeks and started cramping more and started spotting so I went to the er they told me they don't see the sac and that my hormone levels are low it was 157 so the doctor said so basically a 0 he said that I was going threw a miscarriage and I don't  want to believe it I'm 23 years old and today I woke up with more cramping and I started bleeding a lil more what should I do am I going threw a miscarriage  Update I had a miscarriage I'm completely heartbroken