they should not work if you flip them back . Cuz the radian of the front and back side are different . When you flip them back ,they can't coincide with your eyes very well . Also it may cause scrach in your eyes . So you can definitely not flip them .
Yes, you'd better put the right side of the contact lenses in your eyes. Or else, it will hurt your corneal. The water content character will not be worked normally. In addition, your eyes will feel blurry when seeing things. You should take notice of it to avoid the bad effect on your eyes.