How likely is it to get Colosseum tickets in person

i’m going to italy next week and i haven’t bought any tickets for the colosseum just because i wasn’t sure if i was even going to make the trip. Now i can and id really like to visit the colosseum since my stay is in rome but the tickets are sold out for that entire week im there. i’ve heard people talk about waiting for tickets in person, which i dont mind, but i want to make sure that these are tickets for same day entry. I’ve looked through other posts about getting tickets and it seems like they’ve all gotten their tickets weeks before the date.

also any suggestions for site attractions in rome, i plan to do a day trip to pompeii already but something close by that can has same day access.