I don't think that's called for. I think the OP now knows the best thing to do. I don't see how your comment is helping.
I don't think the proposition is ridiculous. Better to ask the question than do something the wrong way.
How is it ever OK to sign a contract on an agreed rent, and then after a few months your not happy and want to just increase it? If you don't think its a ridiculous proposition then nothing I can say.
Leo