Phone crashed while watching a video

I tapped on the screen to watch a video in Safari and the screen flashes black then opened on the homescreen. Since then the phone has behaved strangely. Occasionally slow to take actions. I turned off and on and the apps on the homescreen were blown up for a second. When I open the App Store app there are Feig to grey lines that realign in the footer, with the icons incorrectly spaced.

Any ideas what is going on and what I can do?