Circle Home causing weird IP and port forwarding issues

Question

I am currently living in my parents' house where they have an internet control device called Circle Home. I am trying to set up port forwarding on the router so that I can use Windows RDP when off of my home network. I have set up everything correctly as far as I can tell, but I'm still having issues. When setting a target IP for the port to forward to, I put in the (static) IP for my PC. However, that didn't work, and on further inspection, I discovered that the IP address of my computer, as opposed to the 192.168.1.xxx address that I set, was actually 107.15.168.xxx. Even stranger, when looking up the IP of my other devices, I saw that they had the exact same address as my PC. I know that this is a big no-no in the networking process, so I'm confused as to 1. why it would appear this way and 2. why the network is able to function without getting shared IP errors. How can I get the port to forward correctly through Circle and to my PC? (And no, removing the device isn't an option, my parents basically worship its controlling capabilities)