The quickest way to get back to where you were previously is to literally not worry about it. If you don't worry about it then you'll reduce the likeliness of tilt (Negative mind set which leads to deteriorated performance). All you have to do is play with 100% Effort and have fun. I'm not saying this to be "that guy" because it is actually a necessity. Ignore combo count, Ignore shit misses, Ignore accuracy. Since you were already playing at a higher level a couple days ago, you'll get back there as long as you do not tilt and just play for fun.
That said, at the moment, since you're not playing at your best, play songs you can't pass but are extremely fun, like some 5.5*+ or even a 6* song if you're able. Focus on hitting everything down to the last note even if you miss. If you play all the way through then you'll get your skill back. Join a MP lobby is a good warm-up as well.
As for jumps, it's always better for a small tablet area. Your settings may be different than mine, but I make my tablet area as small as possible. It may be 'too hard' if you haven't done this already, but it's a long term investment and once you get used to it, you'll realize that it's extreme efficient to do so.