You can get the screw rid off the glasses frames with some tools that small enough to do this job. If you can't do it, you can had an optician do this job that get rid off your broken screw in your eyeglasses. Or you can just buy another new pair of eyeglasses instead if you don't want to pay to get them fixed at an eyeglasses store.
First of all, you should see whether the end tip of the broken screw is extending out. If it is, you can use flat tweezer to grip the end tip and then turn anti-clockwise, which will help you get the broken screw out of your glasses. If you cannot get it out of your eyeglasses on your own, you should go back to your optician and ask them to repair it for you. Usually they will use a very thin drill bit and drill it out slowly.
Well, considering your situation. I suggest that you should not get it out if you are not sure enough to fix it. Otherwise, you might get your frame broken. To secure the safety of your frame, you should head toward a glasses store and ask the personnel for help because they are always more professional. But if you have a tiny screw driver, you may also conduct it with care.