my photos can't be deleted nor can it be sent through whatsapp and i also can't screenshot.

i can't screenshot anyth. i can't even delete the photos on my gallery & i can't send any photos/videos through whatsapp. this is so annoying as i need to clear up my gallery. & also, at the storage section in about folder in settings, my photos, videos & music status is showing "LOADING..." & it has been that way even when i restart or on off my phone. PLEASE HELP.