It's quite a time ago, I was already prepared to buy a new one, but then you guys came to my mind - guess I won't lose anything by asking you, and perhaps you could save my money with a better advice than just "buy a new battery".
And by that I mean my ntb has no idea whether it's charged fully or not. Usually it lasts about 5-10min on battery and then dies without noticing it's running out of battery.
So, thank you very much for help and have a nice weekend. I'll definitely come back, as 1) I'll get better in this, and 2) even only for the chat, I like it here.
Um, I really like staying here, you seem to be nice people, but 1) everyone here knows much more about the topic than me (feels bad) and 2) I kinda gotta go, got two gigs in the evening.
Well I went a bit wrong path overally, ended up somewhere in sudo apt-get install perl, and while not being in sudoers, I just bashed my head against a wall a few times and ran for your help.