I Intend To See A Doctor Soon, But I Am

I intend to see a doctor soon, but I am not sure if this is serious enough.

I am 26 and have one child (5). My periods are consistent, five days long every 28 days. I have Multiple Sclerosis(remitting relapsing) diagnosed 03/17/2015 and am overweight (no recent weight gain). My husband and I do not use any contraception.

I had a regular period, then 28 days later I had a very light period. There was no change in flow. For five days I wore just a panty liner and it was only stained slightly pink every day. Now, 33 days later I am late receiving my period. My lower back is very sore and there is a clicking noise when I stand or stretch. It constantly aches with no resolve.

Negative home pregnancy test on the 1st and 2nd days of my expected period.

QUESTION: Does this sound like an early menopause? or Thyroid problem. My body feels aged. I am also curious if this is related to multiple sclerosis.I have felt fatigued, but again MS.

My mother does have fibroids, hereditary? Her periods are heavy however...