Racing thoughts, worry and anxiety can often lead to sleep difficulties. Worrying usually involves involves thoughts about the future. For example, will I be able to clear, will I get the prep done on time; I am going to fail and so on. The answers to these questions is not possible until the event happens however the worry tends to interfere with our functioning.

Don't worry, it is normal to have such anxious feelings when you have stress. Try to do some relaxation exercises. If the anxiety is distressing and hampering your studies you may need to get it treated

It is a normal feeling of anxiety only if it is helping in your performance if it is hampering now in your performance then it needs to be treated

Hello, It is normal to feel like this especially once the exams are close. Try to follow daily routine. Read daily and try some relaxation exercises like yoga etc.