Puppy Regression

I posted about a month ago in regards to having difficulties with my Puppy (Schnoodle). We have had him for over a month and will be 13 weeks. He is doing better in regards to nipping, biting and lunging. He is more of a dominant puppy compared to my beloved past dog. So far, my puppy has been doing well in regards to liking his crate, chewing on his toys (not my furniture), sleeping through the night and house training. As it is super cold & snowy where we are we bought some 'fake grass' that we place by our patio door for the puppy to go potty. It has worked really well. The past few weeks we bought another one outside and put a bell on our door. Our little guy took to that quickly and has done most of his business outside. He will occasionally run to the indoor grass as well.
We had him vet checked a few weeks ago and is a healthy little pup. Unfortunately, he has regressed the past few days in regards to his night time crate and house training. He will whine all night in his crate (and dig) & just wants to be with us. Also, he has been doing his business everywhere in the house. Just after I bring him out, he whines to come in and will pee right on the floor. It has been frustrating as we come to the point where we have allowed him to wander the house with us (never when we are gone!).
I am not sure what is going on......

I would get his urine checked for a UTI (urinary tract infection) - they can occur at any time and very common in puppies.