Smell problem!

Soo I’ve been using my cup over 2 ish years now. I love it and my ability to “forget” about it. Wellll, I kinda ACTUALLY forgot about it.. for like 2 days 😅 I put it in yesterday morning as usual, and the day ended up being insanely busy. And then today, I kind of slept my day away. It was only in the shower this evening that I realized my horrible mishap. So I pulled it out and was instantly met with the most rancid and awful smell. I instantly washed myself off thoroughly and then I washed my cup per my usual routine.. but the smell didn’t come out. So I boiled it. The smell is still there 😭 so now it’s sitting in a bowl of peroxide and water. If this doesn’t take the smell out, what else should I try? I’ve never left it in over 12 hours before, and now I’m crazy paranoid about infection or something. Am I right to be paranoid, or do you think I’ll be okay? I definitely won’t be forgetting about it again 😬