Yeah my specs are
CPU: 3.4GHz
GFX: Nvidia 450
Ram: 8GB
Do you think its not my computer and maybe the game?
well your card can be upgraded, but TBH, unless you're willing to spend $500+ don't even bother. You'll literally be paying XXX amount of dollars for XXX amount of (limited) FPS gain.
I run this game with 2 460's SLI'd and now and again I'll get my FPS crushed. Yes, I have tweaked, twisted, turned knobs etc etc etc. This isn't my first time at the rodeo, if you catch my meaning.
to make it short OP, save your money and buy more games, you'll be happier until you do a FULL system Upgrade.(when needed)