Q: trying to restore my new 6s plus with iTunes, but iTunes says it can't connect

Long story short I got a new 6s plus and left the apple store with it set to backup from my iCloud….however that has taken way too long (over 24hrs) so i stopped the backup and reset it to factory settings. I wanted to back it up with iTunes instead, but when I plugged in my iPhone to my Mac it says the iPhone can't connect because I need the newer version of iTunes. The version i have currently is 12.2.2, and I just used it about two weeks ago to backup my entire phone so I'm not sure why I'm having an issue….i went to iutnes.com  like it said to try and download it but nothing happened? please help me! i am losing my patience with this thing.