Photos is crashing for no reason?

For some reason, Photos (the app) has been crashing as soon as I open it on my iPhone.

I have an iPhone 5s (64 GB) running iOS 8.3.

It started crashing this afternoon. I have, since then, connected my iPhone to my computer, restarted, done a soft reboot, and tried to open it a bunch of times.

iTunes says that my phone has 32.4 GB free and 1.8 GB of photos (6837 photos).

General settings, however, says that I have 30.5 GB free and 4,120 photos.

Like I said, I have no clue why this started happening.