Some bleeding after a hysterectomy
is normal and there should be blood or spotting for at least 6-8 weeks.
The main thing that you should remember and keep in check is that the bleeding should decrease in quantity as the tissues heal. If by any chance there is heavy bleeding, which you should see as bright red blood, report it to your surgeon immediately.
Do make sure to mention the bleeding and spotting to your surgeon on follow up visits.
And coming back to your main question, yes keep sanitary pads on stand by for at least 8 weeks, better safe than sorry.
Hope this helped.