Multiplayer weapon challenges - where are my kills?

Please forgive my ignorance, but I'm new to this game. I'm playing free for all multiplayer online and have just created a class. However, even though I make several kills with my primary weapon, when I go to view the challenges for that weapon, it shows zero kills. What am I missing or doing wrong?

GameSpotScore9.0Editors' Choice
Metacritic Score9467 reviews
User Score8.89894 votes
Your Score- -
hover & click to rate
- 1
- 1.5
- 2
- 2.5
- 3
- 3.5
- 4
- 4.5
- 5
- 5.5
- 6
- 6.5
- 7
- 7.5
- 8
- 8.5
- 9
- 9.5
- 10

GameSpot Walkthrough

Call of Duty: Modern Warfare 2 Walkthrough
Stay frosty with our step-by-step walkthrough for Call of Duty: Modern Warfare 2.
- Go to Online Walkthrough »

Walkthroughs & FAQs

Type	Name	File Size
Other	Multiplayer Guide by Master3203	45K
FAQ/Walkthrough	FAQ/Walkthrough by rata1	67K
FAQ/Walkthrough	FAQ/Walkthrough by sokkus	115K
FAQ/Walkthrough	FAQ/Walkthrough by TheGum	60K
FAQ/Walkthrough	FAQ/Walkthrough by vinheim	218K
Other	Throwing Knife FAQ by GamerSanta	10K
Other	One Man Army Perk Guide by PostxMordem	32K
Other	Sniper Guide by jimmythesnowman	154K
Other	Shotgun Guide by xoChrisiskingox	44K
Other	Sniper Guide by ABrookes	15K
Other	Assault Rifle FAQ by link0099	21K
Other	Hardcore Search and Destroy Guide by Musubiman013	53K
Other	Perk Guide by Stevewins123	33K
Other	Multiplayer FAQ by Prance_Stuard	65K
Other	Multiplayer Weapon Guide by go_monkey897	96K
Other	Multiplayer Challenge Guide by x2xlegixt2xcare	32K
Other	Search and Destroy Guide by TripleJump	81K
Other	Spec Ops Guide by aldecide	115K
Achievement Guide	Achievement Guide by ACowWithaDS and HomieG54	36K
Walkthrough	Walkthrough by drgrady	95K
Other	Enemy Intel Location Guide by Absolute Steve	40K
FAQ/Walkthrough	FAQ/Walkthrough by Absolute Steve	90K