Hcg levels

So yesterday I ended up going to the hospital for a possible miscarriage. I was 5w6d yesterday and I am just wanting to know some more info.

Doctor couldn't confirm a miscarriage but said that it's probably a miscarriage which confused me. My beta test was done last Monday and Wednesday and doubled as normal.

Yesterday they did blood work and said my levels were at 2333 which he said was low given the time frame of where I was at. So that plus the fact that he couldn't see anything on the u/s that he felt I was miscarrying.

Do you think there's still hope since my levels increased just not at a fast rate? Is it too early to have seen anything on the monitor?

8/7- 551

8/9- 1226

8/17- 2333