What do I do I'm so scared

I can't get to a doctor until tomorrow morning and I'm freaking out, I have had a bug bite for a couple days that's painful to the touch and quite large, well anyways today I noticed a red streak develop coming from it. Didn't think much of it until I looked it up and it's a key sign to CELLULITIS?!?! and everything says it's rapid spreading and can kill you but I can't get to a doctor until tomorrow and I'm so scared and I feel helpless