Airport issues.

So check it out.
I bought a refurbished macbook 2010 15 i7 AG Pretty sweet machine.
From day 1 i replaced the hard drive witha momentus XT

After 4 months, since friday i havent been able to connect to the internet, at first i thought it was my router, but my iphone was able to connect, so i restart my macbook 5 times and nothing,so i restart my router 2 times and nothing, after another 6 times of shut downs im finally able to connect my mb to the internet but it craps out on me every other day. is this normal?