a short got removed from my channel, can it be brought back?

check it's actually removed and not just blocked first. if it used popular music, a copyright claim (not a takedown) can block it in some countries or everywhere, and studio shows that differently. a claim isn't a strike, and if you really had the rights to the track you can dispute it from there.

Depends who removed it. Community guidelines removal: you should have an email, and in Studio under Content the short will show the restriction. You can appeal from there, once. If it's upheld that's final. Copyright takedown: that's a counter notification, or ask the claimant to retract. Only counter if you're actually sure you had the rights, it's a legal statement. If you deleted it yourself, there's no trash folder, it's gone. Re-upload from your original file.