I was recently bitten by a mosquito or spider 9/17/16. my upper back arm swelled up and was red from elbow to arm pit. I went to urgent care and was given prednisone, zyrtec, and 2 topical creams. It has since gone down and now I am feeling extremely tired, my neck and upper back ache, my upper abdomen in bloated, and my head feels foggy or something. Is this something I should worry about or will it go away once bite is completely out of my system?