NDX for Diabetes Mellitus Type 2

it seems like I still have problem with NDx. I have my patient is 85yr old; male;
diagnosis: DM type 2, hypertension, leukocytosis, generalized weakness
have edema +1 at low extremities, and complaint pain at low extremities (level 4), using dentures (have swelling gum line), fall last week due to dizziness

base on those I do my ndx like:
1. activity intolerance r/t generalized weakness aeb fall due to dizziness, pain (level 4) and edema on low extremities.
2. impaired oral mucous membrane r/t inflammation secondary to DM aeb difficulty wearing dentures (swelling gum line), decrease tastes.

I dont know y but its just bugging me and I dont fell I do it right.

Any suggestion will help and u make me a better nurse.