2 month old tummy time

So my son turn 2 months old today and hates tummy time now, he use to lift his head and turn side to side but now he doesn’t do anything and I have to old his arms under him or he puts them all the way down to his sides. He will lift it if he’s on my chest but other than that he doesn’t and I’ve seen babies his age completely holding their up on their tummy. He was born at 37 weeks at 5 pounds idk if that could have anything to do with it but makes me feel like it’s my fault for not doing enough tummy time or something. Is he okay though? I know ever baby is different. Any suggestions that could help??