Hind sight is always 20-20. Most likely you should have waited at least 10 days before trying to feed again, and I definitely would have fed a smaller food size. However, I think the regurge was just the start of something more serious. Normally, if you feed too soon, you'd just end up with another regurge, not something like this. I wouldn't blame yourself. I still think it was something more serious, and had nothing to do with the food at all.