I can't log in

Ok I have had this computer for maybe 3 weeks over a year and everything was working great until yesterday maybe around 1 or 2 P.M. and at the time I could login but I couldn't join servers and the server I wanted to join was the hypixel server (ip = mc.hypixel.net) anyway I couldn't join sometimes I joined in and it lasted a minute sometimes a second and then I thought I should delete minecraft I really only play the server so I deleted all files of minecraft everything then I tried again and now I can't login it took me to this page where the background was the dirt thing and it asked me for my username and password so I put it it in and then it began loading and loading and I couldn't get in and also my computer started to get really really slow so I now have deleted minecraft and I don't have it on the computer cause it was making it to slow to use and that's where I am now please help thanks for reading this I want to play again but I'm afraid I can't anymore please help.