My iOS crashed.

My iPhone has turned off and shows a black screen with a download wheel for 4 hours. Should I charge it or, maybe, hope for draining the battery? It was turning off periodically for ~30 seconds last months, storage was full, but when I deleted something the storage mysteriously was full again after few minutes. I freed up some gigabytes in iCloud by deleting iPad photos, but iPhone gallery did not react. I have no access to PC now and there is no Apple repair center in my city (rather town).