Should I be worried?

If you can't handle her using the coupon, maybe you shouldn't have given it to her. It was a gift to her and should not have had any stings attached.

Think of it another way: a child receives a nice gift for their birthday, would you collapse with worry if they began playing with it that very day?

Most likely no need for concern about her, relax.

Not all.

What were the exact entitlements that the coupon bestowed and what was the name of the establishment?

Sounds like the coupon was well overdue.

You definitely want to talk to her about it. How often does she get a chance to have a night out on her own?

She hangs outs with friends when she chooses. There's normally questions from me about the night out and she doesn't like that.

The coupon was for a night out-no questions asked. There have been some trust issues in the past so I was trying to show her I trust her. When she chose to use it so quickly, it just brought up those issues again.