What kind of router do you have?

Go to speedtest.net, what kind of numbers, ping, down, and up?

Can you temporarily connect via Ethernet? Turn off airport if you do. What is speedtest like with Ethernet?

If it is the card, could be, it's doable. The hardest part is releasing the two latches at the top.

Take apart, click on Airport card. In the step where they have you insert a credit card, it's a PIA. I have never had the luck. I just pull the bottom open far enough to be able to get a screwdriver in to flip the latches at the top.

And yes there are external options but run the speed tests, let's see if it is the card, your connection in general...or the son. grin