5 days is fine, some people do every 7, then some do every 3. I started off with every 7, but then I switched to every 5 because I want my anaconda to get a little size on her quicker. Try the frozen thawed, just make sure its fully thawed, and you have the head a bit warmer then the rest of the body, just hold it by the tail and wiggle it in front of your snake, or use tongs if you have them.