I messed up and made a mistake after my 30 day fast.

I finished my 30 day Water Fast and felt great and ate my first fruit (which was watermelon) as soon as I felt natural hunger. It went great and I paced myself for the following four days slowly moving on to nuts and steamed veggies with occasional broths. Day five however, I felt a bit over confident and started eating salted eggs with pepper. Which actually, I wouldn't consider that really bad. I wouldn't consider it good either though. Where I really messed up was deciding to drink milk. It had a funny taste so I thought it was just me not being used to it, until I saw the expiration date. It was expired over a week ago. I felt normal, except I had a bad taste in my mouth, so I thought nothing of it and went to my job at Wendy's (I'm 17 btw) When I got there, I ate some pineapple that I packed along with some cashews. I then decided to sneak a true moo and chug that before my manager saw, and it only went downhill from there. About an hour and a half later, my stomach started to hurt a bit, so I went to the bathroom, and this is where all hell broke loose. I couldn't make a BM, but my stomach was in excruciating pain. I'd even consider it unbearable. I couldn't make anything come out. I had to wait on my body to let me excrete whatever was inside me. It came it waves of horrible pain followed by small portions of diarrhea afterwards. I suffered about 45 minutes of nonstop agony until it was finally over and I ended up clocking out two hours before my shift ended. I feel okay now, but I have read that if you're not careful, your kidneys could suffer permanent damage. I am very scared right now because I do not want my kidneys to be damaged forever at my ripe age of 17 simply because I got a little carried away. What do you suggest I do??