Minus eye power increasing rapidly,

I have minus eye power. It is increasing still now. I am 28, but have eye power of sph -10 in right eye and -7 in left eye. I also have cylindrical power in both the eyes. Why is my power increasing constantly even though am 28 years old? What can I do to stop my power increase? Is LASIK /laser helpful for me? I wear contact lenses at work because I am unable to wear specs made of thick glasses. So I wear lenses for almost 10hours a day. Is contact lenses safe? Is this the reason for power increase? Is this okay? Also will my eye power stop increasing if I stop using computer? Please tell me some do's and don'ts to prevent power increase. Please help me. Also how frequently do I need to go for an eye check up? When I go for eye check up, will I stop wearing contact lenses from the day before?