I used to feel shaky a lot, and it turned out I was anaemic. It's not serious if it's mild and means you have an iron deficiency, so you would need to eat more vegetables ect. I would definitely see your doctor though.
What do you eat? Depending on what it is, you may not be getting the right things that your body needs. Usually things that release energy slowly, like bread and pasta are best. Also make sure you have enough iron, low iron can cause shaking. If that doesn't help, then you probably have hypoglycemia, low blood sugar. In which case you need to go to the doctor, because it's a part of diabetes.
I think you should go to the doctor's, explain the problem and see if they can figure out the exact cause. It's probably nothng serious, but at least then you'll know what the problem is and how to fix it instead of just making educated guesses.
If diabetes runs in the family it's probably best to keep an eye on stuff like this anyway.
Everyone keeps saying "low blood pressure" but I'm not sure if the might mean "low blood sugar." I don't see why eating/not eating would affect your blood pressure, unless they know something I don't.
I get shaky sometimes before lunch. I usually eat oatmeal and coffee for breakfast and both have sugar in it, then I don't eat anything between breakfast and lunch. So I assume it has to do with the sugar I ate for breakfast and getting hungry again.
A few years ago I used to wake up early and drink coffee but not eat anything with it because I wasn't hungry yet, and I would get super shaky and tired and go back to sleep for hours. Then I learned that if I waited a bit to get hungry and ate food with the coffee, this wouldn't happen to me, except for the much more minor occasional happening that I described above.
What time of day does this happen to you? And what do you eat for breakfast? When it happens, are there trends in what you've eaten that day or recently? Like, does it happen only after you haven't eaten for a while, or if you skipped a snack that day, or when you have a breakfast-y lunch?