OTJ 14 days-how often do you test & dental abscess healing very slow

Hello! Pluto's been OTJ 14 full days now (looking back and researching more at the beginning of NS I could have probably still given a partial dose...but looking forward now!). He's usually in the green for AM & PM testing, but we did have one day where both were over 100 on my ReliOn Micro (could have been contraband?).

How often do you test your cats once they are OTJ and in the honeymoon phase?

Also, Pluto had 5 dental extractions on 2/16 (the week of his diagnosis) and had a bad abscess. He was given a Convenia antibiotic shot when I initially took him in on 2/9 (as well as back in Oct 2017 when I took him in for his rabies vaccine and brought up him bad breath). When I took him in a month later for his check up (3/16), the vet mentioned the abscess is healing slowly and I am concerned about it as it's been over a week since then and still looks the same but it is very difficult to look in his mouth very long.

Should I explore a pill antibiotic with the vet? Or has anyone had a similar experience and it just takes awhile to heal because of the diabetes?