Rule #3 on the right of this reddit page. Don't hunt for the hardest maps jesus links to; but understand the mindsets explained by him and various other good players as to how progress works. thelewa's observations on accuracy are imo what you should focus on atm seeing your profile and top ranks; stop DTing for now.
Disregarding that, wall of text now.
I'll disagree will a few comments here; namely those saying "go tackle 5+". He can't fc 4.5+ easily, imo he/she highly needs to work on his self-confidence and adapt his brain to handle the pressure rise when fcing something difficult first of all.
The other reason, his accuracy doesn't seem optimal at all yet; train your % on maps you've already fc'd or ones you love listening to or love the mapping style for. If you were that inactive so you don't remember any specific ones, just press F2 (default 'random map' key) until you find one that's in your level range and you'd like to work on. FCing slightly easier maps will work your focus and even in a short period of time will help you naturally stay on time more consistently.
Play maps under your best-fcs' star ratings. There are some 4~4.5 maps you will have 0% chance of fcing for example because the star system isn't perfect; use it as a reference but know that a Double Monk 4.5 stars Insane is something a lot of 5+ fcers rather not even touch as they don't have the patience to focus/slow down and do 150bpm alt tap.
Just work on nailing 97%+ fcs on those easier insanes, and make your way up. If you find something off when starting OSU! for the day, as Ranguesy mentions, go even under 4 stars in the upper 3s range. Who cares if it's easy in comparison to your best runs, just do a few and it'll do wonders for you. You can even jump to faster bpms or difficulties right after and do much better.
Look at the bpm range as well; don't mash buttons to stream bpms too strong but download maps with lower bpms and try to SS those to work on consistency. I'd even recommend on working on a few specific 120bpm maps for stamina and consistency/focus.
For aiming I recommend varying map choices but this highly depends on how awake&motivated you are. If you realize you can't focus on a specific map anymore even if you try to, leave it be and do another one. Or take a break of 30~60 minutes.
If you just want to get 4 digits rank you could just DT farm and ignore a lot of this. Suit yourself. You'll just get stuck again afterwards.
PM if you want maps; I've gotten past your level recently enough where I still remember precisely what helped me the most.