Increase in marks after valuation cs proffessional

It would be very difficult to say whether there would be increase in your marks. In case you have performed well but due to you ill-luck the examiner has forgot to award you marks in any particular paper, then it may help you. It is all dependent on your luck too. The deficit ranging from 8 to 15 marks  to get increased may be unlinkely to happen, still if its your day, anything is possible.