I did Ghusl for about 5 minutes plus, but I feel like my hair was not washed enough. I was under the shower with water going on my hair for the 5 minutes, but I did not necessarily use my hands to wash it. Does my Ghusl and prayers count?
Bismihi ta'ala
Being under the water for 5 minutes would, in most, if not all cases make water reach all parts of your head, and that would be enough for your ghusl. The important thing is you follow the correct procedure of ghusl, which is head/neck, then right side of body, then left side of body.
Avoiding excessive doubt is also very important.
And Allah knows best