No do not panic about of questions that will or will not come in your upcoming exams, just clear your concepts on trignometry and try to do all the examples of your school textbook. and also do some of the exercise questions.. and the most important thing is buy a book in which you can get all the previous 10 year questions, and then try to solve the question from trignometry and other chapters too.
As far as i rememeber i also had purchased a book by ARIHANT'S PUBLICATION it had all the previous 10 year question..
Do not worry about question paper just try to clear your conccepts and try to do as many questions of different type in trignometry.
trignometry is a very vast subject even many engineers find difficulty in trignometry, so i suggest you to just try to learn all the basic concept of trignometry and practice question based on them so that you dont forget them.
ALL THE BEST FOR YOUR FUTURE EXMAS.