i woke up this morning and blew my nose and
Mostly not serious causes
Hello and welcome in HCM
Yes I can understand your concern
This situation might be from several causes
Usually viral situation or common cold might be the cause.Or when the humidity of the ambient you sleep is low the nose mucosa are stiffened and causes the bleeding.
In such cases it passess soon and probably will not be anymore evident.
Other causes are the use of anticoagulant medications if you are taking them or high values of arterial hypertension.
Nevertheless don't worry so much if you don't have any other signs and symptoms.
Monitor your situation during this days
Hope to have been helpful