Is it Anxiety or are the doctors wrong? Please help.?

OK so I thought I was have a cardiac attack. Went to the ER and checked out great. Then was diagnosed with anxiety. What a load of Bull. Took the medicines for that and they just made me wanna sleep really bad. I have had lightheartedness 24/7 since the incident. They claim this is because of the anxiety. I have looked up the symptoms and it says it causes dizziness or lightheaded feelings but not 24/7. My Mom told me to take some sudafed to see if its ear or sinus related. Well I took the sudafed and it helps when I am on it for a while. Then as it tapers off the dizziness comes back. I hate the side effects of sudafed. I.E. hyperness, sweating, not being able to sleep. So my question is why would the sudafed have helped so much? Is this just because it affected my other senses more or is it indeed some sort of head congestion?