I Have Hard Welts Under My Skin They Appear Every

I have hard welts under my skin they appear every week since July, they itch & are very painful & my hip joints hurt so bad since 2days now. I did extensive blood work nothing has been found......i feel sore & painful all over at times. Could it be spiders or other insects? I would go to sleep & wake up itching & then the hard lump appear under my skin (sometimes my thigh,back, legs, feet, arms, fingers. HELP!!!!!!