Hello. This might sound daft, but almost every day for approximately the past 2 years, I've been drinking instant coffee in the morning. I only have one cup. So here is the issue. I've been using a tablespoon of coffee granules instead of a teaspoon. You are only supposed to use a teaspoon. I only found out yesterday when I looked on the back of the jar. It says to use 1 teaspoon in very small letters. A tablespoon holds roughly 3 times the amount of granules.
I have been having some trouble getting to sleep at night, and I'm wondering if it's from having too much coffee. I've learned my lesson though and will only be using a teaspoon from now on.