Accidents everywhere! Help

Hello!

I am writing this feeling like a failure and not knowing what to do next. I have a 16 weeks old German Sheperd puppy and the last week have been trying to teach him to go outside, as he was using pee pads. Before, he never never had accidents in his crate, but in the last week he ha's been having accidents daily. Not sure why, I try to praise him whenever he goes in the street, as he's currently under medication and the vet advised me to not to take him to parks or close to the grass. I am getting more and more concerned as this is becoming a habit for him. Our routine goes like this: at 04:00 am out, breakfast around 7-8 , as soon as he finishes walk and go out again until 10ish. After that, nap time, again out around 12. Have lunch and wait a little (10 min max) and go out again, to walk. Then, come back to nap time, until 3ish where I took him out, then come back, then out again, dinner, then out again around 8, and final session is around 10-11pm. I try to take him out as much as possible, and give him 10-25 minutes to go. Sometimes, he doesn't even cry just go in the crate, or just pees in the door frame before we leave. I have read that using pee pads is bad in the long-run so not sure what else to do. I will appreciate any help as I am close to meltdown. Thanks and love for all!