Hello-hoping I can help with your question a little. With guys it can really vary on the time frame of when they contact a person they are interested. Especially with you being out of town for awhile, he may not be sure that you are back (correct me if he does know for sure that you are back). Even if he does know, it has only been 3 days. I would give it a week before you write him off. On a second note, if you are interested, text or message him and ask for a casual meet up! You don't have to wait for him!