Photos from MacBook won't upload to iCloud
I have a MacBook Pro 13 inch (2011) running MacOS High Sierra and I have a few thousand photos on the Photos app that I want to upload to iCloud. I bought enough iCloud storage, turned on iCloud in the settings, and waited for them to upload for about a week. When I go to iCloud.com and look at my photos, all my albums from the Photos app are there, but none of the photos. They're just empty albums. There's no progress bar or anything either.
Photos from my iPhone uploaded to iCloud just fine, it's just the ones from my computer that won't work. I had a new hard drive installed on my computer a few years ago, I don't know if that has anything to do with it.
Any ideas why they won't upload? Thanks in advance!
MacBook Pro