Over correction by 1.5, is there an mistake made ?

While most patients have excellent results early after lasik, not all fall into that category. At 1 week post-op, it is still early and the result can be affected by a number of factors including your personal healing rate and your tear film. In general, the way I would treat this would be to increase your tear volume with punctal plugs and to discontinue all anti-inflammatory drops. Additional options would be to start Vitamin C orally and even to place soft contact lenses on the eyes to increase the irritation and cause the corneas to heal in a more robust way. If these approaches do not work, check the cycloplegic refraction and re-treat each cornea based on the results of that measurement.

With a large treatment, it is always possible to be overcorrected. Eight days after surgery is actually quite early, and it is possible that your refraction will drift closer to your target as you heal. While some Optometrists advocate the use of NSAIDS such as Diclofenac as a treatment for over-correction, there is very little real clinical evidence that it is effective.