I drink coffee on weekends with breakfast, I only have 1 cup so it doesn't have as much effect as something like 3 or 4 cups would, but I must say I have had 3

I drink coffee on weekends with breakfast, I only have 1 cup so it doesn't have as much effect as something like 3 or 4 cups would, but I must say I have had 3 cups and I get really shaky and overly inattentive. I do drink black tea though during the week about 3 times a week around 5 o-clock and it usually offers a pretty big boost when I'm feeling tired. I mostly just like the taste though.