Thanks for trying out the game. As for your questions ...
1) In the scene you're referring to with Jennifer (the other mistress), there should be a button with a tick symbol next to the text input field that will advance that part of the story?
2) Body and facial hair always takes three days to grow back. If you shaved your face beforehand, that might be why that seemed to grow back quicker than the rest?
3) Yeah, Heather only gives you two chances - the first meeting at the busstop and the second at the Cafeteria. If you don't shave and wear panties and fail both times, she gives up I'm afraid.
4) Not sure what happened with the cellphone, but in general there's been some issues regarding it for the online version of the game, so I'll be looking into all this before the next update.