I said the wrong thing?

Long story short I have a new teacher. Said teacher was talking about hanging up your feelings at the door and basically putting behind your emotional baggage at the door when you start a new job, during a seminar today. Found out from another teacher who has a big mouth, that this new teachers dog died and I wrote him a letter of condolence (very professional not casual at all) staying I’m sorry for his loss. Now I’m feeling really guilty about it like it’s not my place, I deleted the letter hoping that he didn’t see it yet and I’m wondering if it was a bad call to make. How should deal with this teacher next week?
I said the wrong thing?
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