Well vaginal bleeding after hysterectomy is common for the first four to six weeks after thefull hysterectomy.
After surgery, you might get discharge of old blood clots which have collected from before. But fresh blood should not come.
However as you are suffering from bright red blood heavy bleeding, which is "fresh" blood, indicates a current source of bleeding anf it may require an urgent medical attention.
Any fresh blood, specially when it is associated with abdominal cramping, postoperative needs to be investigated.
And it is foul smell so this could be due an infection which seems the most likely cause.
You must consult your gynaecologist for this.ASAP.
For cough,you can do steam inhalation and saline gargles.
Drink warm liquids.
Use ahumidifier in room.
I hope this helps.
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