There are many symptoms that are blamed on low blood pressure - and some of them may indeed be due to that but the commonest reported problems are:
feeling light headed
feeling dizzy
being tired
feeling fatigue on exertion
fainting transient blurring of vision
transient confusion
mental fogginess
Now - there are many other possible symptoms of low blood pressure but the list above includes those most often reported to doctors. Bear in mind that many of these symptoms also have other possible causes and also bear in mind that the list does not necessarily tell the whole story.
If you have a symptom that you think could be due to low blood pressure then the simplest way to figure things out is to buy yourself a blood pressure monitor and check your readings at the time you have your symptoms. If your levels are low at those times and normal or higher at other times when you don't have symptoms then its reasonable to conclude that your symptoms relate to your blood pressure.
You can find advice about blood pressure monitors elsewhere on this site.