Constant Lightheadedness

My name is Clarise and  I am 31 years old. A few days ago i started feeling a very strong sensation of lightheadedness, as when you sit up too fast from sitting down for a long period of time. But this feeling is constant, all  day every 5 minutes or so. The doctors told me it was an allergy and to take bendryl which only made me very sleepy and hasnt helped with the symptoms at all. Im very concerned it could be heart, brain or even pregnancy related and who should I talk to about my problem?

[CCFheartMD10]

The first thing to do is to establish whether your blood pressure is low. This is a common problem and could be the cause of your symptoms. Measuring the blood pressure both lying and standing is important. Sometimes a more detailed evaluation with tilt table testing can be useful. Other causes of dizziness are middle ear problems, and rarely, neurological problems. Blood pressure can be low in pregnancy, so if you suspect this, it would be a good idea to do a pregnancy test.