If an ECG returns normal does that rule out sick sinus syndrome, and Adams-Stokes syndrome?

I have been having symptoms that make me think I may have one of these conditions. I am fairly unhealthy, dont do much exercise, smoke 5 a day, and after a recent amphetamine induced panic attack (which I feel was a stroke but doctors say otherwise) my heart rate at rest has dropped from 60+ to the mid 40's. Although when I have the ECG it says I am in the low 60's this is simply because I am a bit panicky and then they say everythings fine in a dismissive manner. I am going to get a second opinion but I just wanted to ask on here first. Thanks and god bless.