It has only been a few days, so I wouldn't worry. But I would also stop texting and emailing him. You don't want to seem clingy or high-maintenance. You put the ball in his court, so there is nothing else for you to do. Just do your normal life routine. And if he calls, he calls. If not, don't worry about it and just move forward.
Think of it this way - he had four nights off from work. He spent half of those going on dates with you. Maybe he had other things he had to do that took up the other two days. And now that he is back at work, maybe he is busy trying to catch up.
Just take a deep breath and realize that if he calls or not it isn't that big of a deal. Because you had fun on Saturday and Sunday, right? That's all that matters.
Good luck.
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