My resting pulse, heartbeat is always around 120, so when I just get up from a sitting position, it can easely spike to 180.
I was on a holter monitor for one week and my doctor was amazed, that my heartrate would spike for no reason at all.
When I doze off in my Lazyboy, within 10 minutes I awake shaking and scared to death, because of my heart beating like it is going to jump out of my chest, this is why I have been on Ambien( my very best friend, right after my husband) for 10 years. After I have spend over 6 months of sleeping less than 10 hours in a week. I would wake up with a heart rate of 200 for no reason at all. Of course with a heart rate like that, there is no way you can go back to sleep.
Well the doc finally figured out, that I have Mitral Valve Prolapse, because of the Rheumatic Fever I had as a child.
All this happened, long before I was dx with lupus.
I think your doc should check into it further and not let you do any more of these exercises, until he knows, if there is a problem with your heart.
I may have been dealt a bad hand, but at least I'm still playing with a full deck. ( most of the time anyway).