First thing: If you're doing CF 4-5 days a week, including Buy-ins, Cash-outs, warm-up, and the WODS at a pretty intense level, you're NEVER not going to be sore!! Now, at BrandX they make a distinction between sore and SORE! Sore is ok because it means you've worked out well. This should not prevent you from working out properly. However, being SORE, and for a long time, might require you take a few days off to see why it could be.
Regarding food, and knowing I'm going to bring down Sue's wrath upon me, you should really increase your block count if you haven't already. CF is very demanding and you need to fix your muscles after a workout and on your rest day. Increasing your block count will provide enough protein for this, keep you inside the zone, and give you that extra amount of calories you need to not go into starvation mode, where the body will start taking from the muscle to keep up with your physical demands. Fat-wise I increase it 2X or even 3X depending on the WOD. You should be well inside the zone at this point so maybe your energy levels have to do with sleep? Or else with not having increased your block number. I'm also in the 16 block a day range but I've upped it to 20 and follow the 3-on 1-off program, scaling the WODs according to BrandX.
Other than this if you can provide some more info as Sue has said then we might be able to help you further.