Cindy, do phone your vet to strong advocate for getting pain under control for a 20lbs dog. Lettie can't heal properly when she is battling unnecessary pain.
Gabapentin for nerve pain has room to
move up in mgs dose 3x/day
methocarbamol for muscle spasm pain — if giving the entire 500mgs tablet that is too high.
Double check the bottle for the dose in mgs you are to give 3x/day
Tramadol-
advocate this addition as the general analgesic. The usual in controlling pain is to Rx at the higher end of the mg range AND promptly every 8 hours. 20lbs =
9.07 kg Something is very wrong if your dog has not pooped since Dec 31 going on 4 days now! The longer poop stays in the intestine the more moisture is absorbed, the harder poop becomes. If she is not wanting to poop because it hurts, all the more to get the meds corrected today, asap.
PUMPKIN
Plain pureed canned pumpkin is a magical fruit - its high fiber can firm up stools and help with diarrhea or loosen the stool to help with constipation.
NOTE: alternatives are really ripe mashed fresh pear, just take off the peel off; microwaved and mashed peeled sweet potatoe
--
To loosen the stool, add equal parts water to each kibble meal and soak overnight. At mealtime add one teaspoon of plain canned pureed pumpkin 1x a day.
-- To firm up the stool add 2 teaspoons plain canned pureed pumpkin 1x a day to soaked kibble.
PEPCID AC
Not eating, drinking are likely
red flag indicators of Galliprant damage to the stomach lining. This needs attention today.
When you confirm over the phone with your vet no health issues such as liver, kidney or heart, then go to grocery to pick up Pepcid AC (one active ingredient- Famotadine) Give Pepcid AC (famotidine) 10mgs tablet twice a day. Know about protection of the stomach with any anti-inflammatory drug:
dodgerslist.com/2020/04/18/steroids-vs-nsaids/WATER INTAKE
About 3 cups of water per day for a 20-pound dog. The water is a combined total of both moisture contained in the food and liquid intake.
-- Provide a frozen homemade broth ice cube to lick on during the day
Homemade meat broth (no salt, no onion) will inspire her to drink on her own, eat better? Simmer a hamburger patty or some chicken parts (neck, wing, back, leg) with water to cover. You can freeze the broth to serve as an ice cube for licking enjoyment on OR slightly warm the broth for an inviting fragrance to want to lap up or pour over a meal. Save meat to crumble a teaspoon or two on top of a meal for extra tastiness.
Discard chicken bones and skin skin. Cool in fridge, remove fat disc from top of jellied broth.
This tip to attach water and food bowl at head height inside of recovery suite is one of many tips to learn about the details of strict rest for a disc episode:
dodgerslist.com/2020/05/14/strict-rest-recovery-process/ 
please update to ease our mind her pain meds were adjusted (how?), stomach protection is now onboard (Pepcid AC-famotidine), and dose of methocarbamol?
How old is Lettie?
