We had what seemed like a great time, told me they would call and never did. What happened, did I do something wrong?
Well as much as it hurts to hear, they just didn't want to. This is one of the times when dating can be disdainfully simple. While it doesn't make it any easier, it's okay. Actually it's better than okay because they probably aren't "The One".
Most people who have smartphones are attached to them like a newborn baby. We are next to the phone literally all day and night, waiting for that dopamine hit in the form of a notification. Messages, chats, texts, emails, calls; all at our disposal for communication. If they really wanted to, they would have.
I like to think of callbacks like the lottery. If you found out you won the Jackpot, would you not cash in the ticket? I highly doubt it. Similarly as to when you really like someone. You probably would act immediately, showing your interest and anticipating the next time to spend together. So if someone ignores you, you can expect that they aren't the one. Relationships are a two way street, you just gotta be able to read the signs.
Your best bet is to get back out there! Have fun, don't hold too put pressure on yourself or the timing. The person for you is out there!