2 1/2 year old grunting

All the sudden my son has started grunting and point instead of talking. It’s not all the time. Usually after reminding him several times I need him to use his words he’ll stop. It’s starting to worry me though. Is it a normal phase for that age? I try to play it off as him being lazy or just being to tired to talk but he’s never done this before. Our doctor doesn’t seem concerned but I wanted to see if anyone else has experienced this with their kiddos.