About a year ago, I finished my Master’s thesis, which was supervised by one professor from my university, and two people from a different university. One of the two is a professor, but he was not involved much in the daily supervision. When finishing up my thesis and presentation, times were quite hectic, and only now I realised I may have never thanked the professor from the other university as he was not present at my presentation. I did approach him for a reference letter later, and thanked him for that when letting him know I got the job.
Now I feel quite rude, but I am not sure if I should do anything. Mostly, I am afraid of it being awkward if I bring this up after a year. Am I overreacting? What would you recommend?