Irrationally Upset

So my husband is overseas and I'm 34 weeks pregnant. Both of these circumstances combined have made me really paranoid and self conscious recently. I'm so scared that he's going to cheat on me, and if not cheat than at least flirt with other girls in person or on the Internet. He is not the kind of guy that would cheat at all but back in December when we were ttc I found some texts on his phone that made me really upset. It was the middle of the night and I couldn't sleep. I heard a notification for a game go off on his phone and decided to open it and play. After a while I got bored of it, and I don't know why, but I decided to look through his texts. Not all of them, just the ones between him and his roommate from AIT. I never really met his roommate or other friends so I was kind of curious as to who this guy was. The majority of the messages weren't really significant at all until they started taking about a girl that was flirting with my husband. The roommate said something along the lines of "she wants to have sex with you" and my husband said, "that would be fun". The conversation ended at that but it made me so mad that I woke him up and asked about it. I was cheated on in the past so I am very paranoid. He assured me that he didn't mean what he said and hat he was just going along with what his roommate was saying because he wanted to become friends with him. I believed him but it still kind of bothers me to this day. Anyway, today I was looking at his Facebook page because his birthday was the other day and I wanted to see what people were writing in his wall. I noticed that he was following someone, only one person, a girl. At first I thought it might just be someone he went to high school with but I got curious and decided to look at her page. They weren't even friends, he just was randomly following her. She's a really attractive African American cosplayer and I'm actually really jealous of her. My husband is Hispanic and before we started dating, the only girls he was really into we're black or Asian cosplayers with really nice bodies. I am neither black nor Asian and I don't think I have a good body at all. Even when I wasn't pregnant I was still a big blob of flesh compared to this girl. I know it's kind of petty to be upset about him following a girl on Facebook but I am just so stressed out right now. I've been having a lot of anxiety attacks because of stress at work and with my schooling and this just made it worse. I don't know what to do. I don't want to annoy him with my constant paranoia but I also really don't want to be cheated on again, especially not while being married and having a child.