Hi April,
If your steroids can make your potassium go low then it can give you arrhythmias and palpitations, I take diuretics which lower potassium and I ended up in hospital with arrhythmias, I have an underlying heart problem so it made it worse (that doesn't mean to say that you will though)
You could eat lots of foods that are high in potassium sich as bananas but I would suggest get a blood test first to see what it is because if your potassium level goes to high it can also cause problems.
It is best to get it checked out first. Its not a major problem but because it is an electrolyte imbalance it throws the body out of sync.
I hope you get it sorted.
Linsay