Wireless....cannot connect....not receiving packets, only sending them.

I have a laptop and it found a wireless network that I could connect to. I presume it is a wifi hotspot. Anyway, I have been able to connect to it, even with a low signal strength for about a month, but since yesterday, it has not worked properly. My laptop detects the signal, but the two little computers that flash blue at the bottom of my screen dont flash together any more. It is only one flashing blue, and the other not. When I clicked on it, it showed that I am sending 'packets' but not receiving any. Is there a way to fix this? I clicked 'repair' when I right clicked the 2 little computers but that didnt not fix the probelm...instead it said, cannot renew IP address. Please help, I need the Internet at home!!