I don't know if I'm doing this right.

I'm 39F, 172cm/100kg. Right now I'm averaging \~ 1250-1350 cal daily, meal prepping everything and weighing meticulously (whole foods, fresh and natural ingredients and delicious because I love cooking) and I'm satisfied (I get normal hunger signs from my body now instead of "I'm bored/sad, let's eat) but I don't know if I'm in a correct calorie deficit? I've used like 5 TDEE calculators and they all have wildly different results. They've been saying to be in a deficit anywhere between 1200 and 1500 etc. I have lost a few lbs since starting a month ago. I will say I'm not hitting the gym or anything, I have some serious chronic pain issues (degenerative disc disease, I've had several spinal surgeries) but I am a vet nurse in a surgery hospital so I'm on my feet 12+hrs 4 days a week and lift more than I should on any given day, so I feel like that counts as "light activity", right? I also do a lot of walking in cemeteries on my off time doing genealogy work. I really want to lose weight not just to feel better about my appearance but mostly to put less stress on my spine and hips. I used to be underweight but gained a LOT from a thyroid disorder and it's meds along with not being able to consistently exercise from the spinal pain. I just don't understand if I'm eating too much/enough because I don't know if I'm doing the math wrong.