I'm no expert but 2 weeks withtout eating isn't a very long time to be overly concerned. I'm sure in the wild most snake species can survive much longer without a meal if necessary.
The fact that it appears to be losing weight and that its regurging would alarm me. A can't imagine any snake looking thin & losing weight so quickly only after a two week period since its last meal. Also, I am not sure why you fed her a larger prey item after she regurged a smaller one (hopper...mouse, I assume). That could be a cause to her 3rd regurge. You may not have allowed it enough time to regain strength after her last two regurges. They lose digestive enzymes & probably important digestive bacteria when they regurge. I had a problem with a one-time regurge and it never happened after that. Probably due to temps or too large a prey item in my case. I soaked mine in a container with warm gaterade to replenish electrolytes. However, I don't know if thats the best thing in your case.
If I were you, I would take her to a vet and try to collect fecal samples to take with you for the vet to run tests on. I certainly wouldn't keep trying to feed it. Sounds like it could be something more serious but you did not provide info on your setup & temps. Also, I would start documenting & record keeping if you have not already. Keep track if it defecates and also weigh it every couple of days to see, in fact, how much weight loss it is experiencing.
"i have a 5 months old boa that have not eaten a whole meal in 2 weeks. i have feed her a frozen mouse. she regurgtated, a hopper she regurgitated too. and a full grown mouse and the same. what's going on. she is getting quite thin. please let me know what it could be and what i can do thanks"
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