Don't worry, Andy. Maybe you can try using data recovery software. If your computer can't detect your phone, try to open the USB debugging on your phone device. Then follow the steps as below:
Step1. Download Android Data Recovery and install it.
Step2. Select the files where you want to recover your data from and click "Scan" button.
Step3. Preview and select the files you want to recover. This provide a lot convenience for users who want to do Android Photo Recovery
Step4. Click "Recover" button to save the recovered files to the destination folder.
Read more about how to recover deleted files on Android. After these steps you could successfully finish the recovery process. As I said it is quite easy, right?