Hi Latasha -

There could be several things wrong. I suggest you take your car to get checked as soon as you can to prevent additional damage, or what's worse, the possiblity of getting hurt should something happen to the car while you're at speed on the road.

It most likely is an alignment issue. Your wheels (tires and rims) are properly weighted so that they rotate in balance. If the weight is off at a certain rotation speed it may cause a vibration/shaking, while at other speeds it won't.

It may also be a deformation in the tire itself, or perhaps something different with the axel or part of the brakes.

Like I said, best thing you could do is drive a little slower until you can have it checked out by a professional.

Hope this helps and stay safe! Itay.