Any ideas on why i'm so sleepy all the time? could my melatonin levels be too high?

Sleepiness: Having excessive daytime sleepiness could indicate a sleep disorder. It is recommended you consult a sleep medicine specialist who can review your history to determine if that is the case. For example, if you also snore, have dry mouth, morning headaches, and periodically stop breathing throughout the night with gasping episodes, you may have sleep apnea.