Q: Why do my photos on my iPhone 5s need to buffer?

I've had my iPhone 5s for about 2 1/2 years now, but within the past 6 months, every time I try to look through my library for old photos or videos, they seem to need to buffer, or load. I'm not trying to view them on my computer, like other threads have seemed to ask. I always keep my phone updated to the most recent version as possible and have 2GB of storage free on my phone. Please help me with my issue, thank you!