Nursery hidden camera/recorder

Does anyone know if I can kit my son up with recorder or camera at nursery. I am heartbroken I found my son inside the nursery room sitting on a chair all alone sulking looking like he’d been crying since I left him he was like this last Tuesday with the same nursery assistants. He did not want to be left with them he never touched his food said he tried. He’s been with no food since half 12-6pm didn’t offer no snacks nor milk. My son looks big for his age he’s not even 2 and half yet I get the feeling he’s being treated differently by these staff he doesn’t know how to talk ask for things. I brought my son home he’s showing my his feet he’s got big painful bruise both his feet. Which none of staff even told me if he’d a fall. When I left him one of the staff wasn’t on the greatest mood she goes o I really could do with sleep she’s grumpy no smiles on her grumpy face. He barely was out to play kept coming back inside sat on the chair obv waiting for me. Gave him milk in the car I knew they’d doing this to my son. He drank like he’s not eaten all day when I asked him did u eat he said no. No one even cares he was inside alone looked as if my son wasn’t getting any interaction communication to even encourage him to play if he’s inside with puzzles or clay etc atleast someone should have been inside with him. The cry when he so me was the same as last Tuesday. The rest of the days he’s been fine going to nursery. Do I just take their word he’s been ok good well looks like not to me.