You can speak to God at any time, in any place He will always listen!
Don't worry about people thinking you're crazy. I was talking to one of my friends yesterday who thinks I'm a nutcase. I told him Jesus was coming back and he said if Jesus turned up again, he'd buy a hat and eat it! He is trying to convert me to nihilism. He is very good at arguing and I often can't respond to his arguments, but it doesn't mean he won!