HELP! I think I just ruined my chance with a guy I really like 😓

Okay so to put it out there I'm okay with casual sex and I usually still stay friends with people I hooked up with (they're mostly my friends) and there is nothing going on between us.

One of the guys I had sex with is my best friend, let's just call him Alan. We are really close and despite the fact that we had sex before almost a year ago, he's still one of my bestest friends.

Then I started liking this guy a lot, we went on dates etc. We got really close and one day he stayed over at my place. We were talking and I told him I have a journal that I write down the things I do that day. He was curious so I showed him it thinking I have nothing to hide.

He knew I was good friends with Alan, and Alan gave me a quick call before when the guy I like was over.

When he was looking at my journal, it happened to land on the day I had sex with Alan and I wrote down "Had sex with Alan" there. The guy I've been seeing saw that and said, "Oh was it the guy who called you earlier?"

I also told him before I was going to visit Alan for the holidays for a few days because he lives in another city 3 hours away.

And I said, "Yes. But nothing is going on between us, we're just really good friends"

Which was true.

I don't think anything changed, but the day after that he started messaging me less and less. Cancelled on a date, and I haven't seen him in 2 weeks after that. He hasn't messaged me in 2 days now too. I think that was the problem.

I don't know how to explain that nothing is going on, although I can understand how it may seem shady to him but I feel like just because I had sex with someone I ruined my chance to be with anyone else if I stay friends with them??? What should I do?