Masterbate?

Do you masterbate even tho you have a fiance? My fiancé is on his way out of town and I'm so soooo horny. Ever since I hit 27 weeks pregnant (I'm 28 weeks today) iv been horny all the time now.. we've been together 2 years and I hadn't masterbated since we've been together so I feel like it might be wrong to do so🤔😶😶 I just got off the phone with him and his voice turned me on even more😭😭