So I decided to play minecraft one day after like 4 months of not playing it. I knew that 1.9 was out I just didnt play it because I didnt really want to play minecraft. Anyways so I opened the launcher and I was signed out for some reason, but when I entered my password it didnt work. I was 100% sure my information was correct because when I bought my account I wrote it down so I wouldnt forget it. After retyping my information like 22 times I decided to go to the minecraft website ( minecraft.net ) Haha I dont know why I didnt think of that in the first place XD! So apperently the ychanged the password stuff so you have to have 8 characters instead of 6. So all I had to do was change my password! I hope this helped you if the same thing happened!!!