I was following the advice of preheating @ 400 and had every intention of lowering he temp to 300 but instead I forgot to lower it and ended up cooking it for the first 30mins at 400. I just lowered the temp to 300 and flipped it. How should I proceed?
Without a thermometer (which I personally do not own), the other way of testing pork to make sure it is sufficiently cooked is to pierce it with a fork or skewer in the thickest part.
Check this extract from recipetips.com:
Piercing: Another method for testing doneness is to prick the cut of pork with a fork or the tip of a knife and check to see if the juices that escape run clear. If the juices are clear or have just a very faint pink tint, the meat is done. If the juices are not clear, the meat should be returned to the heat source for further cooking.