DO NOT FEED HIM FOR 3 WEEKS. Wait and allow his system to recover and repair itself. It is vitally important that you follow these instructions to prevent your snake from regurging again. This is extremely hard on a snake and they can damage themselves. Chronic regurging often leads to death. Surinams are known for regurging and, as such, a first regurge is a little early for a vet visit.
Wait that 3 weeks then offer him a fuzzy mouse. That is going to be a tiny meal, but he'll need to eat tiny for awhile. If he keeps that down, wait 2 weeks and feed another fuzzy mouse. If he continues to keep that down, feed a fuzzy mouse every 10 days for the next 4 feedings before very slowly upping the prey size. Keep him on mice for a while - mice have less fat in them and are generally easier for the snake to digest. You can switch him back to rats when he gets up to an adult sized mouse so long as he doesn't regurge again. If this doesn't work, then a vet visit is in order for a fecal exam and checkup.
Also, keep handling to the absolute barest minimum during this time too. Only handle if you absolutely have to. You recently had to treat him for mites and the stress of that coupled with handling after feeding (yes, I know it was 3 days later, but that could've been enough) was most likely the cause. The good news here is that the regurge is likely due to stress and not illness.
My sunglow arabesque just regurged this week too. I will be following the same protocol. We can commisserate together....![]()