FIXED!!!!
For anyone who has this problem, do this:
1. turn off ubuntu
2. take out the external HDD
3. put in a Windows disk
4. boot into the windows disk, like u did to install ubuntu
5. wait for everything to load
6. press the R button
7. select partition 1, or whatever
8. type "fixmbr" and press enter
9. type "y" and press enter
10. reboot. fixed!