Joining a CC is probably the best thing you can do here.
You meet new friends and you find people you can trust to play AS / MP.
There are more tournaments to play (for free and credits) so you get more XP.
You have a source of advice, most CCs have plenty of members willing to give you plenty of good advice. (Usually without the snipes you get on the main forums).
So, yes, join a CC, just try and pick one with a good range of tiers and plenty of active (very important) members. Many CCs have a large membership but often the biggest factor to how much fun they are is the activity of the membership not the size.