Hi, Im Almost 51 & I've Noticed That My Periods

Hi, Im almost 51 & i've noticed that my periods vary. This month it was very heavy but last month I only had a pinkish smear for 3 days. However, I've noticed that the last few periods carry an offensive odor after day 4 for about 3-4 more days, even as the blood flow ends. I am worried about this.