macbook internet troubles - out of nowhere

i just got back home from a weekend at my dads, and my mac is now having some issues... this morning i managed to log on to the internet for about 30 minutes before it froze up on me. i closed firefox to restart it, but it wouldnt load my home page this time.. i closed my screen and walked away for 10 minutes. i came back and opened up the screen and waited for it to connect. several minutes later, my computer was STILL scanning for a network.. ive connected to the internet SEVERAL SEVERAL times from this room within the past 4 months, but now all of a sudden i cant.. i opened up the networking tab in system preferences to see if anything obvious was messed up.. i couldnt find anything, but as soon as i closed out of system preferences, my computer finally connected to my wireless modem. i immediately opened firefox and activity monitor.. my home page STILL wouldnt load and the activity monitor said firefox was only transferring 1 bit/second every 10 seconds (so really the average would be 0.1 bit/second).. i closed firefox and my computer and walked away again, and when i came back, my computer now cant even find my network at all, period. ive been waiting now for several minutes... when it actually has connected, i have a full signal. so why the **** cant i connect to the internet anymore?? im typing this discussion on my iphone.. this is ridiculous.. i cant find any help anywhere on the internet.. i just love it how this technology never has any simple problems...... any help would be amazing, ive got math homework to do on the internet, and i cant afford to drop this class on account of my crappy apple technology..