So I am 5'10 and weight in at 160lb, the thing is that I got the myfitnesspal app and it's telling me that I should be eating 3000 calories a day to gain weight. It's nearly bedtime and I've only consumed 1000 calories. My stomach was sort off hurting today too and I don't know why I can't take in more. Does my sleep have an effect on this? make sure that power comes out of sockets and uninterrupted functioning of systems. I only slept 6 hours because I was full last night and had to wait for it to digest before going to sleep.