My aunt passed away on may 9th and i've been experiencing palpitations and light headedness when i wake from sleep. what can be causing this?

Anxiety from stress: This sounds likely to be a reaction to the stress you are under from your recent loss. Increased anxiety causes Adrenalin surges which result in palpitations and light headedness. Would talk to your doctor. Avoid stimulants like caffeine and keep alcohol to a minimum. Stay well hydrated. You might need a mild anxiety aid lie xanax (alprazolam) or an antidepressant for a time. Cardiac tests if sx continue.