Guy I like 'liked' then 'unliked' my photo on Facebook?

[boltonbird1984]

I asked a guy out by sending a private message on FB. He didn't reply but a few days later he 'liked' a photo of me early in the evening. The 'like' was there for a good 18 hours and then I noticed it disappeared. He is still on my friends list, and other likes on the same photo are still there. I know that one of his friends has fraped him a couple of times late in the evening/early hours, but can't decide whether this like was a frape or not.

I'm not going to send him another pm in case he thinks I'm desperate!

Wth?
The photo he liked was my current profile pic of a head shot of me on a night out. We have 2 mutual friends including his Step Sister