I am 42. The last 2 months my period has come early and this month it is over a week late. Yesterday I went to the restroom and there was blood in my stool. Is this normal and/or a stage of menopause? I have taken 3 pregnancy tests and all 3 are negative.

Menopause can have all sorts of indications, and yours sound typical, except for blood in stools.
The blood in stools might be hemorrhoids either inside or outside, but to be on the safe side, make a regular non-emergency appt to see your doctor. If they are h's and get really bothersome a simple outpatient surgery can be done.

I sometimes have blood in my stool just before my period

I will give a guarded response to that: some women do bleed rectally during their period. Doctors might test for endometriosis, polyps, anal fissures, but most will just say it's hemorrhoids that are affected by your hormones fluctuating. Maybe the tendency to bloat (retain water) puts pressure on them and they bleed more - just a guess.
You can find other women discussing it by googling 'bloody stools menstruating' or similar.