Do you sometimes feel like you've slept longer than you have+have you figured a reason/pattern to this ie deeper sleep,more dreams?

I don't sleep that much/well, hard to get to sleep+wake up easily, but sometimes it happens to me+I feel like it must be later than it is, like if I've slept 4 hours I'm surprised cos I think it must be later. I don't feel better or anything but I feel inside like for a long time I've desperately needed even a little bit of extra sleep.