Replying to So that was stupid.

So my bud got left in my car from last night.
Unfornunately thats the car my dad took to work today before i realized.
SO. the bud is in a headphones case that doesn't look suspecious at all, but i left my bright red lighter right next to it. which might draw attention.
Right after school i'm planning to drive over to his office and nab it, hoping he hasn't noticed it yet. (Its right in the open compartment under the CD player)
However, if he does notice, and confronts me, what's my response?
Anyone had to deal with this before?