Am I being unreasonable?

Jessica • I`m 28, I married my sweet husband in Oct of 2014, I’ve got a DD born March 2016, and we’re TTC #2
I have had this argument with my husband many times. Normally I just get mildly annoyed since there isn't an emergency. He is constantly turning his phone on silent or leaving it at home when he goes to work out and I need him for something (drs appt, insurance info, etc) I have told him many times that he can use the do not disturb function of his phone and leave me on as alway ring.  I get he isn't alway the most handy with technology, but really it's not that hard. And I know he doesn't forget to turn it back on on purpose, but it's really starting to piss me off. I have told him that he needs to learn to not to forget and use the do not disturb cause I'm getting close to delivering now. The idea that I could be going into labor and can't get a hold of him or in an emergency and can't, terrifies me. I know I'm a little overly emotional right now with all the hormones, and more irritable due to a lack of sleep and the constant back pain, but is it really that unreasonable for me to be upset with him for this since I've told him my fears and that time and time again he still forgets? I just really needed to vent and see if maybe it's just my preggo hormones going crazy or if I really have a point.