it will collapse
The most common site for a blood draw is the antecubital vein.
Vein
She could be missing the vein or be agains a valve in the vein
median cephalic vein
You insert it into a vein to draw blood.
Heck yes you can! I am a medic in the army and I've done quite a few IV sticks on the veins on the top of the foot. I haven't drawn any blood from the foot but there's enough pressure down there to do so.
You could miss the vein
you never draw BLOOD from an infant from the baby
There are three veins to choose from when drawing blood. The first choice is Median Cubital. Second is Cephalic vein and lastly the Basilic vein.
That means that the needle they were using to draw your blood when through the vein instead of stopping while in the vein( needed to collect the blood) and fluid leaked out around the vein. It will stop its own leak and will eventually heal itself. Ice will help the swelling for a short period.
There is no such thing as arterial blood gas. When they draw blood it is drawn into a vial that has a vacuum, so it may appear that they are drawing gas, but no such gas exists. Also, when they draw blood they draw it from a vein.