Baby not moving

When I am supposed to call and go to my doctor when the baby doesn’t move?

After how many hours should I start to worry? 😕

Can a baby just have a sleepy day and not being so active?

I am 28weeks btw. I haven’t felt kicks today when I usually do just very VERY light moves that I am not even sure are from him.

When he kicks I know it is the baby, now not so sure.

I have been eating and drinking all day, usually after I eat I feel him today not so much 😞