Why hasn't he called

I saw a profile on Grindr, and recognized he's my colleague and have a crush on for a long time. I didn't know he was guy.. So we hooked up.. I think we had a good time. Afterwards, when i asked him if he wanted to meet again, he said sure, but would like to be friends only. I am totally fine with it, since I'm not really looking for a relationship (but open to it if meeting the right guy). But since then, he never really asked me or actively contacted me... I am a little obsessed now, and can't stop thinking about him.. should I move on? I see him at work almost every day...