Localized hives for over one week.

I had surgery on June 25th.  The nurse who inserted my original IV caused a very large bruise on the left forearm.  I have no idea what she did, but prior to inserting the IV, she injected something to numb the area.  Lidocaine (sp?), I believe.  The area was very swollen and very dark purple in color.  
Last week while at a BBQ my forearm started to itch.  I noticed where the large bruise was (now faded about 75%) I had developed hives, or numerous small blisters.  I m not worried and my doctor does not seemed concerned either.  
However......  It's, 8 days after the rash/hives first started, the blisters are now spreading to the inside of my upper arm and down to my palm.  But, the thing that's scaring me is the sharp pains I keep having (only in the past 12 hours).  These pains are very pin-point, stabbing pains on the inside of my left arm (where the rash is) about 6 inches from the elbow, mid-arm.  I have no idea if there is a connection or not or if I'm just over-reacting.
Any feedback would be very much appreciated!
Thank you.

[Dr_Aparna]

Hi,
The itching and blistering rash could be part of the allergic reaction.Contact dermatitis is an inflammation of the skin caused by direct contact with an irritating substance.
Irritant dermatitis, the most common type of contact dermatitis, involves inflammation resulting from contact with acids, alkaline materials such as soaps and detergents, solvents, or other chemicals.

Skin lesion or rash at the site of exposure could be of any type: redness, rash, papules (pimple-like), vesicles, and bullae (blisters).
The treatment is usually with application of a Corticosteroid ointment.

The presence of pain /tingling could be a part of the dermatitis, though it is not a comon complaint or it could be due to some other viral/bacterial infection which require an examination. This could include a biopsy to rule out any other skin inflammatory condition.
Once the accurate diagnosis is made only then the appropriate treatment can be decided upon.
ref:http://www.myonlinewellness.com/topic/adam1000869