Do I deserve time alone outside of the home?

I dont have friends to discuss this with but i want to know if I'm being unreasonable. I have 15 month old twin girls and life is very stressful for me with being a new mom, working full time, and being in a struggling relationship. Eveytime i leave the house, my bf has something to so. "Your moms gonna be gone 3 hours" or make it quick or just rushing me. If I'm gone for 3 hours I went to a lot of different places because at this point I forced myself to stay in the house all week because I don't want to hear his mouth. So the day where I do go out and live my life it takes some time. I'm an introvert so I enjoy alone time. He thinks there's no way I can be gone 3 hours, he assumes I'm cheating. I'm a woman and some of us like to shop. If I had friends I'm sure I would have shopping trips sometimes.  I'm with the twins alone all the time and I would never complain if he chose to you know go do something for a few hours I probably would be happy because hes annoying lol Today I went to CVS, the bank and to target, probably gone 2 hours. I was getting food, supplies, decor for the house. I dont even shop for myself really. He called twice asking me how long I would be joking that he was making sure I'm alive and when I got home he called me making jokes about me sitting in the car. Like I can't even sit in the car. Am I being unreasonable being gone for 3 hours or so once a week if that? I'm always paranoid when I leave looking at how long I've been gone, telling myself what I can't do because of time. I think it's ridiculous.