Discover Card Summons-what do I do?

I was recently summomed by "nathan and nathan p.c.",out of birmingham alabama(anyone heard of them? are they actual lawyers or debt collection center) for a debt owed to discover card that I am approx. 6/7mnths behind on. On the occasions I did speak to discover, I asked them to give me to the first of this year, when i would get my income tax back and could pay to get caught up. Other times they had called, asking for me and my 15yr old son answered(who has a deep voice). Apparently thinking he was the "MAN" of the house they preceeded to tell him i was behind in payments and wanted him to authorize payment on the acct(which is in my name only). I had told them to NOT speak to anyone but me, but, again, and it must have been someone different that called, proceeded to think my son was my husband, (and i dont have one). And tell him, that i was behind and that he needed to authorize payment on this. I have never been summoned and dont know what to do...he said i had to respond within 14 days and i asked him where it said to that on the paper, because all i seen what the court date which is in March. He never gave me an answer. What do I have to respond to within 14 days. I tried to offer them 1500. with lower payments, but their idea of lower was 250. a month. the bill is (or should i say was) 2200. He was almost like a calm bullier. Any and all help is greatly appreciated. and i thank u all so much for answering.