Only going forewaed 2

[Lostmygirltofish]

I took the top off the motor and shifted it in reverse and when it goes back it gets too a certain point and then it kicks back foreward. Also is it normal to see a little gas in the water when you stop like a film in the water. I'm trying to figure out if i have a slow leak, becasue i put 10 gallons of gas in the boat and probably ran about 10 miles and ran out of gas. Does it burn more gas if the oil is out or low? I have 16.9 foot Hydra Sport flats.

Thanks for the help.