when to take my cat in?

Hello all. i am not sure how to word this as i am worried sick about my cat (i am very dramatic). A few days ago my cat threw up a few times, once it was white foam and then the other time it was a hair ball. he didn’t eat dinner, which is so weird for him because he usually eats anything and everything in site, and he was extra sleepy. since then he’s been alright. but today he has been sleeping all day. he ate earlier, but once his feeder went off for dinner he didn’t eat anything which again, is not normal for him. i know him so well that i can tell he is not his normal self. he usually plays, runs around, and is active. but again today he has been sleeping all day and has been acting off. i’m going to call the vet tomorrow morning and see if they can squeeze him in. so far no other symptoms but i am just extremely worried about him. i am able to afford care so it’s not an issue for me. he is relatively young as well, he just turned 6. i’ve had him over a year now, he’s never showed signs of being sick ever so i am just extra worried. i apologize if this is all over the place i just am wondering if this could be nothing. thank you.