I sometimes get a heart rate between 110 - 120 bpm without doing any exercise, i often feel light headed and my hands start to shake at the same time?

Panic Attack: At that heart rate, your heart is probably reacting to a stimulus rather than being the cause. Your best diagnosis would be a reaction of your body to stress or a panic attack. If you are breathing fast at the time, that can cause lightheadedness and shaking of the hands. When this happens, try to hold your breath or at least slow it down and relax. If it persists, you should see a doctor.