Whenever i drink coffee after 20-30 minutes i get muscle weakness, sleepiness, and tired why?

Adverse reaction?: Perhaps, you have an allergy or a sensitivity to coffee. Other possibilities include reactions to flavors- if a flavored coffee, to the choice of cream or creamer, or to the choice of sweetener. (You can try to isolate by checking if there is a reaction when tasting just one of the individual ingredients and monitoring your symptoms, if this applies.) Maybe you will need to stop drinking coffee.