It's only been 2 weeks...
I'd argue that you don't have to mention this job at all. When asked why you're job searching you can explain why you left your previous position.
If you're in a region where you can't omit a job from your work history no matter how short, you can be honest without going into details:
I'm leaving my current job because the position changed significantly after I started.
This is true: you took the job because you were expecting a raise and now that raise isn't going to happen. But you don't have to mention that the significant change was about compensation.
This is a common enough situation that they ought not to press you further.