When is it ok to worry?

Well today was our second trip to Sick Kids with my soon to be 6 year old daughter.  Our first was a result of a walk in clinic back at the beginning of January with all 3 of my children who were not feeling well and ended up being sick with Strep Throat.  During that particular visit the doctor discovered my little girl had a heart murmur that she described as metallic ( whatever the heck that means) so she writes up a referral and tells us we HAVE to get our daughter down to Sick Kids Hospital that day! So after spending a couple hours already at the walk in clinic we drag all 3 kids down to Sick Kids Hospital to get her checked out.  Keeping in mind that all 3 of my children are already sick and not feeling their best.  We wait 14 hours YES 14 hours before they let us go home! They did all the usual tests ECG ECO Chest X ray and tell us it's nothing to worry about just a innocent heart murmur but there is some swelling around the walls of her heart and to just give her some Advil for a few days.  2 days later they call us and say that she has to go back to Sick Kids to see the Head of Cardio!!  So by now I'm thinking what did they miss?  So we go today, wait and wait and finally are seen and the doctor checks her out and decides that he does hear something and is almost positive he knows what the cause is ( MVP) but orders yet another ECO to determine exactly the amount of damage or whatever we are dealing with.  Which won't be done until NEXT week! So here I am a worried mother having to wait yet another week to find out if her baby girl is ok or if we are in this for the long haul!!
Now I know I am probably being an over protective mama but this is my baby girl we are talking about here!! I think I have every right to be freaked out and worried just a tiny bit!!!  After all what mother wouldn't be right?