Hello and welcome to the forum:
The symptoms you describe are somewhat "nonspecific". And while they could be consistent with heart failure, all considering the chances are certainly higher that it is not heart failure. A couple of suggestions:
1. Regarding the "racing heart", you might want to consider a 24-48 hour holter monitor. This would monitor your heart rate over a couple of days and may allow for the diagnosis of an arrhythmia or reassurance that all is ok.
2. If you symptoms of swelling, fatigue, palpitations persist, I dont think it would be unreasonable for a referral to a cardiologist for a more thorough assessment and probably an echocardiogram. A BNP lab test can be very helpful in this instance as well (not sure if this was checked by the ER).
Wishing you well.
Best,
Dr. Rich
I would also like to add that my heart rate is usually around 64-76 but sometimes even around 84. And when I am up and down the stairs it can go up to 140 but then usually drops back down to around 80-90 within about a minute or two. But usually its around 68 I would say. It was staying at around 84 for a while but recently has been in the 60's