Why would he do all that then ghost me?

We hooked up
green flags
he said he had that post sex glow after it.
I complimented his eye colour after and he looked into my eyes and smiled and tilted his head back
he told me “am I really never gonna see you again I can’t believe I’m never gonna see you again” (he was touring with a band from US im in Scotland he left the next day to go next city)
he told me he’d be back in October
he asked for my social media and posted a picture of us to his story / highlights reel
he laughed at my jokes and I caught him watching me
..
red flags
I haven’t heard from him since
his friend who I met that night who was supposed to be into my friend followed my Instagram too
he was trying to get me to be on my way after the hook up
.
i think I might’ve caused it by appearing distant afterward my goodbye was very very quick and awkward and I just quickly hugged him and scooted off whilst he kind of held onto the hug
Why would he do all that then ghost me?
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