Is the refractive surgery a risky thing to do?

No: Unless you are a poor candidate (various reasons). If you have a stable low amount of a simple, regular refractive error with a normal thick cornea and a healthy eye plus informed reasonable expectations, then the risk is small.

No: Although every medical procedure carries a degree of risk, the chances of ending up with worse vision than before the procedure is rare. In order to minimize the risks, you should seek out a surgeon who performs a large number of these procedures (thousands) and do not be afraid to ask about his/her results with patients who had a prescription similar to yours.