He left... now what?

I let hubby go in his first boys trip to Vegas. He’s 28 and has never gone away with friends just me and him usually. We’ve lived together for 8 years and I’ve never been away from him for 4 plus nights. I feel all depressed now that he his gone. Our son is staying with his grandparents in another town for 2 weeks so it is just me. I’m 18 weeks pregnant and I don’t know what to do with myself now! Kinda sad I know lol. But what are some good ways to make the time pass by? I don’t want to be calling or texting him. He needs to have a good time. Just feeling emotional.