Welcome and congrats! I'm a military wife/Vet.
My last pregnancy with my DD I was in the exact same shoes as you. DH came home for R&R and I got pregnant in those 2 weeks by an opps (pull out method) I found out I was pregnant after he had already left. Waited an entire week for him to call me from Iraq so I could give him the news. Thankfully he made it home in my last trimester and was there for the birth. Gotta love our R&R baby. It was rough him being gone for most of the pregnancy and then when he did get back in the last part of the pregnancy it was me having to take care of him with the migranes he gets. Hope we can be some supprot for you.