Problems with my wifi

So I have a 13-inch Macbook Pro, late 2011. I've never really had many big wi-fi problems until now. Just two days ago, my wifi was working perfectly well. Then, at night, I lifted my Macbook's screen from sleep and connected to our wifi. My laptop has always been able to remember the wifi password, but then a notification popped up asking for the password. I entered the password (correctly), and it loaded but could not connect. I entered the password some more and it still didn't connect. I did't know why, because the password was definitely correct. I thought it might have had something to do with my keychain, so I opened Keychain Access and found the password for the wifi. It was correct and the same exact one that I entered. So I deleted all saved info on the wifi's password, cleaned out my system multiple times with CleanMyMac, and then relauched my finder. After that, I restarted the system two times. Then I logged out and back in, the entire time with the wifi shut off. After logging back in, I cleaned out the system again and turned on the wifi. I connected to the same wifi network as I did the day before and entered the password while clicking "Remember password in keychain". Finally, it worked. But not for long. The same problem rose up minutes later. I think there is something wrong with my laptop. Anyone experience something similar? If so, do you have any advice that could possibly solve this problem? Thank you!