Quitting Pain Pills, How long will it take my brain/ head to feel good again?

Hey all, 

I'm not much of an outgoing person so this is different for me seeking to talk to someone. 

I am 27 years old. I have had 2 lower back surgeries. ABout a year ago I reinjured my back and started taking 5/325 Hydrocodone. About 4 months ago they switched me to 5/325 oxycodones. They help with the pain but I'm always running out a week before my refill. I've borrowed from a a friend a few times who has some medical problems. (I was on Tramadol for 1.5 years before this, but stopped use of that about 2 months ago)

I got promoted to one of the most stressful jobs in the company about a year ago. I haven't felt the same since the move, and I'm not sure to attribute that to pain pills? I'm always nervous about getting another refill because my body hurts. I recently just tried a few rounds of trigger point injections and they seem to be helping. I have been contemplating if the reason i've felt more depressed this year is because of the continual use of pain meds.. and maybe they are messing with my bodies ability to make "feel good" vibes on their own. Well, I flushed what i had left of my oxy's about 48 hours ago. I can tell i'm seeing some withdrawl signs, but trying to get through it. Not going to go into detail, but about the same symptoms everyone has. I feel even more depressed the past few days without them.. and super lazy. Hard to get up in the am.. and social anxiety like crazy. I freak out everytime my phone rings. 

Not totally sure if it was the pills but I don't think they were helping by any means. Willing to give anything a try, I just got engaged and want to be a better partner and not feel like sh*t all the time and have moods swings. Or feel I need to be on my meds to get work/house sh*t done, or dull anxiety. 

How long will it take my brain/head to feel good again? Any tips or advice is appreciated.