Potential ectopic or chemical pregnancy

Hello - new to this and very keen for any advice I had a FET on the 16th June, 5 day blastocyst, tested positive 9 days later but low HCG 30, not a good start, then only increased to 32 in the next 48hrs, then 146. Referred from the clinic who said it's almost certain not a viable pregnancy to the early pregnancy unit who did a scan and said far too early to tell, at 4.5weeks now and have to go back in a week for another scan - aaarrrgh what do I think?