According to Vastu Shashtra the toilet above office room is not suitable for you. You should change the office at other place. If it is not possible than you should follow under given following tips :
1. You should cover the office welling with plywood or red cloths.
2. A yellow colour bulb should be fix in South East corner in office.
3. Your seating place in South West corner and facing North or East is best.
4. If you have a computer / Laptop etc than these articles should be in front of your face.
5. Your side table, file and etc should be beside of your right side.