Had Stage 0 Cancer. Medication Prescribed Anastrozole 1mg Generic For

Had stage 0 cancer. medication prescribed anastrozole 1mg generic for arimidex 1mg daily for 5 years. I 'm 72 years old and very active and enjoy life, however taking this medication since Februray 16 at night with1 Vitimin D3 1000 iu. my hip joint, thigh and knee aches really bad and wakes me at night. I don't feel like my old self any more.
Stopped taking them for 3 days and feel good and energetic again. is this dosage too strong for me? I see my Surgeon on the 22nd of this month.