Podcasts won't refresh and I am randomly unsubscribed.

Whenever I open iTunes I find that I have been randomly unsubscribed from half of my podcasts and all the episodes have been deleted. I try to resubscribe but every time I click the 'subscribe' button in the iTunes store nothing changes. The little box will pop up asking if I want to subscribe, but when I click yes I'm still not subscribed and no recent episodes will download. Additionally, whenever I try to refresh my remaining podcasts nothing happens (I've checked them in the iTunes store and the store says I'm not subscribed, but when I try to resubscribe once again nothing changes). And whenever I open up iTunes on my computer I get a barrage of messages like this: "iTunes can’t verify the identity of the server “init.itunes.apple.com”." I'm not sure if they're related or not. I've attached a screenshot of one of the error messages, I usually get multiple ones with a different link/server/whatever it is in the quotes.

Does anyone know what is happening?