I haven’t heard from my Girlfriend in boot camp

My girlfriend left for boot camp (Navy) on April 4th. We have been talking through letters and her once a week phone calls (Saturday). I’m starting to get worried because it’s been a week since our last phone call and I also haven’t received any letters in a week . It’s already hard not having her here, but to go this long without communicating makes me feel anxious. Should I be worried? What should I do? She graduates June 5th btw