Don't be scared. Just tell the truth and keep your friend next to you if you get intimidated quickly.
You seem very sensitive. By giving the items back people will know you're telling the truth.
As long as you know you're honest& took nothing, don't worry so much about what others think.
Have your friend give the phone back or give it back yourself in the presence of your friends. Explain what happened- then let it go.
If they don't believe you, then the problem is with THEM NOT WITH YOU.