is a very common problem and most people suffer from it at some point in their lives. Caffeine is often the culprit for sleep problems
so I would recommend cutting back on your consumption. However, I do not recommend cutting caffeine out completely all at once as this can cause pretty severe withdrawal symptoms such as pounding headaches. Cut out one drink a day for a few days and then gradually cut back more and more. I do not recommend having any caffeine after 2pm.
There are many other things that could be causing your sleep problems so I recommend scheduling an appointment with your primary care provider to discuss your symptoms. In the meantime here are some suggestions for getting a good night of sleep. Try to go to bed and wake up at the same time every day, even on weekends. Make sure your room is the right temperature (most people sleep better in a slightly cool room) and darkened. If you cannot fall asleep within 30 minutes, get out of bed and do something else for 30 minutes and then try again. A regular exercise can help with sleep but don't exercise within the 2 hours before bed. Good luck!