Your question actually relates to the wider issue of learning to practise efficiently, so it may help if I summarise some points I made in response to another post in this regard recently.
I find myself that setting aside enough time to practise is difficult with work committments (I am a full time music teacher who only occasionally gives piano recitals these days), but I do make the time. Trying to maximise the efficiency of practice is absolutely crucial. For example, not wasting time just playing the same difficult passage over and over, tripping up at same places, physically or mentally or both; rather, drilling down to the problem, identifying it, then working hard to fix it through very focussed and intensive practice. This sometimes involves adjusting the fingerings as well as slow practice, gradually building up to the required speed and then placing back into the context of the whole passage or movement. This approach is nothing new of course, but I am very rigid with it given the limited time I can find to practise properly. I cannot afford to waste time just playing through pieces making the same mistakes, indeed as you say, seemingly getting worse. A common problem for every musician potentially, unless you develop more efficient, analytical practice techniques.
An anecdote I heard years ago was about a landlady who was excited to be renting a room to a concert pianist, who clearly was looking for a room with a piano. She expected to hear her own private concert recital by listening at the door. She was regularly disappointed because all she ever seemed to hear was endless scales, arpeggios and general excercises, and bits here and there of real pieces of music, very short sections of which just seemed to be repeated over and over and over again. This story may be slightly apocryphal; nevertheless, it does illustrate the point I made earlier about 'drilling down to the technical problem', analysing it and trying to resolve the persistent mistakes(s) systematically.
Wrong choice of fingerings are often the root cause of technical difficulties in playing a passage of music. The more you play it, the more the inappropriate fingerings start to create problems with accuracy and fluency. Correct fingerings are absolutely crucial, but not crucially absolute. At the end of the day you should try out alternatives and eventually settle on the finger choices which feel most natural and comfortable for you (not necessarily those in the score, which more often than not are suggestions from the editor, not the original composer. Even suggestions from Beethoven and Chopin for example, who were pretty meticulous with fingering passages, are not necessarily comfortable for everyone, with different sized hands or length of fingers) However, once you have tried out alternatives and finally settled on your chosen fingerings, then you must stick to them in all subsequent practice. Constantly changing fingerings will only add even more confusion in the long run.
I absolutely agree with the idea of studying away from the piano with the score, imagining your way through a piece. This also helps when memorising. A teacher once said to me when I was a piano student at London University studying performance as part of the B.Mus. degree, "you do not know a melodic passage until you can play every note from memory with only one finger." I thought at the time he was being rather pedantic, until I heard him play a recital at the Royal Festival Hall, in which he was virtually note perfect, with excellent attention to detail throughout in terms of dynamics, phrasing and expression, as well as his overall accuracy and fluency.
My main concern is that, during practice, there will inevitably come a point where your efficiency will decline through fatigue and loss of concentration. Shorter bursts of effort, say up to an hour at a time with at least a 20min break, are far more beneficial than constantly practising, in the hope that pushing yourself hard lke a marathon will yield great improvements. Not necessarily. This is not a race. In fact, this is the law of diminishing returns once physical and mental fatigue set in! Instead, practise for shorter sessions, and each chunk of maybe up to an hour or so, should have a different focus, whether excercises, different pieces, sections within the same piece etc I have learned a lot from mistakes I have made in the past with my practice habits over the last 40 years or so. There is more advice I could offer, but at this stage see how you get on with these basic tips with regard to improving the efficiency of your practice. Good luck.
Topic: What time to take a break during practice?