Unplanned report to HR

I went on a work trip with a coworker that I see maybe once a week, once every other week. While on the overnight trip, I felt very uncomfortable with the person. The realization hit harder when I was back home that (31 F) I do not want to travel with this person (61 M) again. I initially vented to a coworker who suggested I talk to my boss and the guys boss. I had pl ned on talking to my boss just so I could avoid traveling with them again. My boss also suggested we pull in the guys boss. So I talked to his boss too. Now the guys boss talked to HR and I have a meeting with HR about the incident tomorrow. I didn’t expect this to turn into a whole big thing. And he’ll find out it was me because I was the only one on the trip. I’m nervous to see the guy again after all this. Luckily my coworker I vented to initially said he had my back, and my boss and the guys boss were on my side. Any advice, words or experiences people had would be much appreciated.