Dear,
Don't be panicked. The topics you need to study of physics and chemistry in neet is provided in the official website of neet.Try refering to it. These are your class 11th & 12th portions only. You shouldn't be tensed. You don't need to study anything apart from these.  Try solving more questions related to these topics.Use more reference books .For example you can use ARIHANT PUBLICATION, CENGAGE,E.RODOV, N.AVASTI,PRADEEP and many other to practice and make your basics more strong.

Keep calm . Clear all you  doubts. Just study your  11th and 12th class chemistry and physics syllabus.Make a timetable.Try appearing online test series conducted by different coaching institutes.You will get aquainted with the question and have a practice of how to solve during the time of the real examination.I am sure you will do well.
Best of luck.