We'll TB we now have something in common! I get them on/off, mostly without warning when your not expecting it.
Been to docs a few times after having bad ones, got one years ago when I was in work and I really did think I was going to hit the deck - light headed proper couldn't get a breath with that one - that one was my worst but that's cause I couldn't leave work I'd to stick it out.
Please please please, be very carful with them tabs your on, i fecking hate them