I've just had EC (last Wed) and not experienced this. I did experience it during D/R and realised it was down to Chinese food I had eaten that same night which due to high salt and colourings etc this caused me to have your symptons for the whole night. (not sure whether the drugs reacted?)
I'm no expert but if you still have your symptons keep ringing your clinic and stress the importance of someone calling you back ASAP. If no response try NHS helpline. I used them recently and they were really good.
Thanks for your replys - I went and seen me GP instead at 11.30. He thought it could be a mini panic attack but I am on Prostap injection and one of the side affects is palpatations. He also said it could have been triggered by a bad dream which might make sense since I dont normally dream and when I woke at 5am I could believe the dreams I had like my husband worked in a shoe shop instead of the outsourcing company!!!!!! I havent been affected by the drugs but I think it hasnt helped on this ocassion.
I am sometimes woken up by the same thing. Rapid heart beat and shallow breathing. For me it is anxiety/panic attacks. I get it during the day too. It probably happens once a week and more often when I am overtired (which has been a lot recently). I have found that taking Bach Rescue Remedy helps to get me through an attack and Kalms help to relax me so they happen less often. Don't take anything while you are having treatment though unless the clinic have ok'd it. I once had an attack so bad that I was hooked up to heart monitors until they were sure it wasn't more serious. Then they gave me betablockers in case I had another bad attack. I have never taken them though !