is your company is it 100% local 51% local or 100% foreign... if its 100% foreign, then there is no way that you can change your job title...
expats always fall for this, it is easier for the company to bring someone on a "Technician Visa" so they would bring the person fast without going through the hassle of attesting his education certificates in his home country and here in Qatar. but its too late now, if your company is local or semi local you would be able to change your job title in your visa after 1 year of employement (end of your contract), in the other hand if your company is 100% foreign, then there is no possible way to get this through.