Should i take fosamax? menopausal &my lower back hurts after 4hrs of high heels seated at a dinner reception.?

i have been 4 years menopause (2006) and my calcium intake is not regular. i always had lower lower back weakness since age 35. however, i was shocked to feel that my calcium bone deterioration might b on fast track since i hav a hard time looking as being seated straight unless i consciously straighten my back.. For pictures I was surprised to hav found 1 picture that showed me hunchbacked despite my thought that i was just being normal in posture.