2nd day after my cat's euthanasia. I miss him even more, does it get better?

Yesterday I took my cat of 5 years for euthanasia because he was diagnosed 6 months ago with heart failure and had valentine's heart so he started meds, he made it for 6 months more but yesterday it was his last day. Struggled with breathing and stopped eating, force fed for 3 days but he didn't get any better. The vet said that there is nothing we can do anymore.

I was there when they put him down and cried all day yesterday and didn't sleep because of crying and feeling so sad. Buried him in my yard with his favorite toy.

Now it's the second day and it feels so weird that he didn't wake me up and do his cute purr, that he isn't in the kitchen rubbing on me and waiting for food, he isn't next to me when I'm watching TV, I'm writing this with my heart broke i can't continue writing. I'm SAD