Mail has stopped responding

Apoligies to anyone who read my earlier post (Worried my iCloud account has been hacked), but I thought this title might be more appropriate (and get possible replies for me, and help for anyone else in the same boat too).

See screenshot for the popup dialog box with the (potentially hacking?) message and link.

Grateful for any help or ideas with this - I'm really worried as a few other odd things have been happening too :-(

Many thanks,

Janet

Original post:

Hi Everyone, Hopefully someone can advise on this (I'd be really grateful)...

This morning I clicked on an 'unsubscribe' link in an email (The Hut Group). A blank webpage appeared, with a url which just seemed a long list of characters (unfortunately I didn't record it in anyway). I then logged in to my iCloud account and clicked on Mail - my mail was there as expected, and I started to look for a rule to try to see if there was an additional way of stopping the annoying spam I'd been receiving (from The Hut Group) from downloading from the server. Before I even managed to locate anything I got a popup dialog box telling me that my 'Mail has stopped responding'. I've attached a screenshot of it (with iCloud mail in the background). I clicked on the 'Send to Apple' link without thinking. I'm now wondering if this wasn't a genuine iCloud error at all, and it was in fact a phishing hack to obtain my apple ID info and email? :-( I didn't think to hover over the 'Send to Apple' link to check that the url looked ok. Has anyone else had this? Does anyone know if it is a genuine iCloud link? ...I'm currently in the process of changing passwords etc - it's going to be a long day :-(

Thanks,

Janet