You must have pressed CTRL+A, tip(1) ``raise character'', specially designed for people with broken Caps Lock keys. Use ~s as above and set the variable ``raisechar'' to something reasonable. In fact, you can set it to the same as the force character, if you never expect to use either of these features.
Here is a sample .tiprc file perfect for Emacs users who need to type CTRL+2 and CTRL+A a lot:
The ^^ is SHIFT+CTRL+6.