Wi-Fi connectivity being weird. Please Help!

Hello,

Lately I've been having an extremely frustrating problem with my Macbook Pro (late 2011). It started when I connected to my wi-fi network. I connect and an exclamation mark appears on the wi-fi icon. I clicked on it and it said "alert no internet connection". So then I went to system prefrences to see what the problem is. It said "Wi-fi has the self-assigned IP address {a weird IP address that I didn't recognize} and will not be able to connect to the internet". So I figured I could change the IP address in TCP/IP to fix the issue. I got my IP address and entered it in. So then I went back and it said "Wi-Fi is connected to {my wi-fi network} and has the IP address {my IP address}. It looked like everything worked. However, I instantly became dissapointed when I looked at the top of my screen and It still said "alert no internet connection" and it still had the exclamation mark on the icon. I'm very confused, I have no idea why this is happening. I would appreciate it if someone replied to this and helped me out 🙂