Downloading iPhone photo's to iMac

The OCD part of me likes to keep all my photo's organised on my iMac. We all know the issues of the poor among us who only have a 16Gb iPhone and the dreaded 'storage almost full' when trying to take photo's. I used to regularly plug my phone into my iMac and download all the pictures, and filter them into relevant albums. Since I clicked "optimise storage" I haven't had to do that for ages. Fantastic. I can take as many pictures of my cat as I like. But now I have some free time I've plugged my phone into the iMac and opened photo's. In the "My Name iPhone" tab it's only giving me the option to import 17 new photo's. A few from today and the rest are from months ago. There's also nothing in"My Photo Stream" (However the photo's have made their way to my iPad.)

So after doing some googling I found out that I haven't selected iCloud Photo Library on my iMac. I have however, selected My Photo Stream in the same menu. So I click it and it tells me that the free 5GB is not enough. I need to pay for 50Gb to back up my entire photo library. I don't want to do this. I have my photo's backed up on an external hard drive so I do not need them also backed up in the cloud.

So. How do I get my photo's out of the iCloud and onto my iMac? I have tried using iCloud.com but after passing the two step identification it's telling me I also need to verify the email address that I use for Apple (the very one I've used since the first iPhone) and I'm currently 3 hours into the wait period for an email with a six digit verification code. I have checked my junk folder regularly too. What am I doing wrong that is preventing my photo stream on the iMac from working?