Think I'm having a breakdown

So today I had to go outside for the first time in 6 months and it was only a few doors down from my house. I had no contact with anybody without a mask but now I can't stop thinking really worrying thoughts and can't stop shaking! Think I'm freaking out! 

Also the parcel contained some food items, ( pepsi cans, bread etc) and I don't know if I can get myself to eat/drink them now because I'm worried because they were left on a neighbor doorstep and I'm getting really paranoid. 

Sorry If I don't make much sense