The "points" you see are basically hlstats, a ranking system which reacts to your kills/deaths/defuses/bomb plants/rounds won and kill streaks. It's separate and different from the ingame point system CSGO uses.
(HLstats is like the "overall server ranking" [it's a plugin that the server owner/admin loads up when they set up the server] while the ingame points that you see if you view the scoreboard while playing [tab key] are there just to determine who wins the current session)
 
If your kill/death ratio is good, you will lose a large amount of points when you die and you gain very little when you kill a player/bot, but if you keep getting good streaks (7-10 kills per death) you can climb up. It's a bit easier to get points if you play on the casual server if compared to the Death match server, because you don't die as much.
 
If I died on the DM server I usually ended up losing 20 points per death and gaining only 2-4 points per kill, headshots give you +1 points per kill if the killing blow is in head. Honestly you shouldn't even think about the points cause it just makes you play worse. Your score fluctuates a lot in the beginning because the system doesn't have much info to "give you points" on (the k/d ratio plays a part here). It's a really a good system if you think longterm, it will balance itself out if you just keep on playing.
 
This is where you can see the points and all other stats such as k/d ratio, kills per minute, online time and so forth:
evgagaming.com/stats-source.aspx
 
You can click on the CSGO then click on the "Players" tab.