Everyone is different, some people join a band within weeks others never get there, most will go from day one to a fairly simple blues covers type band within 6 months to a year as a guess? The wanting to get better never really ends and there is more than a single life times worth of learning out there so be prepared for never ending searching for nailing something new! I have been playing nearly 30 years starting in acoustic guitar lessons at primary school, I have a lesson booked in for next Sunday!
Enjoy it, start going to a few jam nights and meeting people, you will be amazed how much a goal focuses the mind and practicing time, even if you dont get up and play for a year from now you can start learning a few numbers your local jam night does then turn up one week and ask to play three numbers from the list you have got or even ask if you could just join in on mustang sally or whatever, as a house bassist I would be more than happy to let you do one song then me jump on for the next two for example.
The only problem I can see and it is not really a problem anyway is that I wish I had nailed scales, theory, reading etc etc first but like most I just wanted to get out there and gig, now years later I am having to do it backwards to understand what I have been doing all these years! That is just me though, I know some people say they are happy with what they do, no intenetion now of doing anything else and no need no learn any new skills to be busy out there playing for example.
Dont worry about messy playing, it just takes more time and practice and like I said once you tidy up one aspect of your playing you will find the next thing wrong or you will want to learn slap or use a pick or use fingers or buy a fretless, it is never ending but it is good fun