Cramping

So im on my 2nd pregnancy at the moment.. Had one miscarriage in may and im currently 5 weeks and 4 days.. I’ve been having severe cramping and went into the ER and got labs done and an ultrasound. My levels were well over 15000. My ultrasound showed a gestational sac and a small yolk sac. My last pregnancy at the same week only showed a gestational sac.. My doctor is concerned it’s either implantation cramping or the start of a miscarriage.. I’ve had absolutely no bleeding but the cramping has gone on for almost a week now. Let me know if anyone has any advice. This has been eating me alive