how have you revised so far, for example I have been doing about 6 hours per day with a past paper per day, reviewing it, working on weaknesses and filling gaps in content. Also remember you will never feel 100% ready for your exam, there will always be that one point you can't remember etc. but you don't need 100% for a top grade so just focus on doing as much as you can to control the outcome as best as you can. Also providing you hours are productive, 7 hours is more than I would say 90% of students do for exams so your fine