Thanks for writing in.
I read your problem,i would like to tell you that bleeding gum indicates gum inflammation
,which could be because of so many factors like-
1.Ill fitting dentures.
2.Deposits on tooth surface,restoration and denture.
3.Vitamin k and c deficiency.
4.Medications like-calcium channel blockers,nasal sprays etc....
You said that you use to brush twice daily,it does not mean that there is no deposit on your tooth surface.
So i will suggest you visit a dentist
in your area as soon as possible and get the thorough examination done and take a proper treatment and go for scaling if needed.
Nothing to get worried.