Don't worry about it, I've been as high as 7k and still felt the same things you do. I would randomly freeze up and not hit the key, or miss notes that didn't require me to move my cursor, or randomly miss an entire slider. I missed notes on 4 star songs so often I wondered what was wrong with me.
I feel a lot better about my play now (even though my rank is quite a bit lower) and here's what I did:
1. Stop thinking about rank, comparing yourself to others, what playcount is good, and having to get pp in general
2. Play a huge variety of songs. Pure stream, jump practices, alternating, high BPM, low BPM, high AR, low AR, dubstep, HR, DT, whatever. Don't give up on a map just because you aren't doing well on it.
3. Finish maps even when you screw up
The key idea here is that if you tunnel on pp, you aren't really going to get the range of skills that help you become a flexible and consistent player. This isn't to say that pp and skill are mutually exclusive (they're obviously not), but that playing songs that won't earn you pp is a really valuable experience.
I feel a lot better about my play now (even though my rank is quite a bit lower) and here's what I did:
1. Stop thinking about rank, comparing yourself to others, what playcount is good, and having to get pp in general
2. Play a huge variety of songs. Pure stream, jump practices, alternating, high BPM, low BPM, high AR, low AR, dubstep, HR, DT, whatever. Don't give up on a map just because you aren't doing well on it.
3. Finish maps even when you screw up
The key idea here is that if you tunnel on pp, you aren't really going to get the range of skills that help you become a flexible and consistent player. This isn't to say that pp and skill are mutually exclusive (they're obviously not), but that playing songs that won't earn you pp is a really valuable experience.