Help with hcg levels

I had blood tests done on the 9th sept to check my hcg levels due to a chemical back in march..they came back at 99.8,

I had another on the 11th and it came back at 99....my doctor has told me there is no point doing any more tests as it probably won’t stick but I’m not so sure,my pregnancy test i did today is darker than any of the others,i feel sick i have sore boobs i have missed my period by 5 days now and am 18dpo...the nurse said the first result was pretty high for 3 days passed missed period.

Has this happened to you? Did you go on to be pregnant?or should i face the inevitable and wait for my period to show?