Hi.. Thanks for the query.. Your symptoms are appearing to be due to allergic reaction to the antibiotic amoxicillin as rashes and hives is one of the common presentation of antibiotic allergy.. Although it appears to be a delayed reaction as it happened after about a week of antibiotic intake.. If you are still taking antibiotics then you should stop taking the same and take anti allergics like Benadryl or Levocetrizine.. Apply Calamine lotion over the skin to sooth the skin.. Do cool compresses over the rashes.. You can also consult an Emergency room and get a steroid shot and also they can advise alternate antibiotics if you still need the same.. Hope this helps.. Regards..