Pharmacist gave my 11 month old infant wrong doseage, I missed a week of work and my son was violently ill!?

My son was seen by his dr w/ otitis media 12/10/2008. He was given Augmentin 1 & 1/2 tsp twice daily. The doctor gave me a hand written script. My husband stopped at the Kroger pharmacy & had the script filled. My husband gave my son several doses before I actually had an opportunity to check the bottle. When I did administer a dose to my son, I noticed the strength seemed high for a 17 pound 11 month old baby. Augmentin 600 mg 1 & 1/2 tsp twice daily. I called Kroger the pharmacist who told me my son was given a hi dose due to his infection being chronic, I questioned this diagnosis since it was only his 2nd ear infect in life & requested a copy of the original RX, it was written Augmentin 125/5 1&1/2 tsp twice daily, the correct dose. It was a pharmacy error, they offered me a gift card "to make this go away". My son had 8 days of severe diarrhea and vomitting, followed by a week of lethargy. His 1st xmas was a mess and his 3 sisters suffered as well missing family parties.
I ran out of room to write. A settlement group contacted me and wants to know what I want or how much I think it’s worth. At 1st I was a little mad, all I wanted was my son to be correctly treated. I have been communicating with a settlement group for a couple months, they always say they will call back, but never do. My son has had to have liver function tests to confirm no long term damage. I’m just frustrated. I do feel like they should be responsible, but how do you place a value on what might have happened. He was very sick for 2 weeks and I missed 1 week of work. More than anything an apology would have been nice from the pharmacist. I still can’t believe she lied to me and passed the buck to my sons dr.
My question is how do I value a claim of this nature? Why should I have to be the one to determine that value?