I think i might be trans

My story short, when i was 5 i used to close my eyes and thinking about myself being a girl, lay on floor and daydreaming until my mother seen me and asked me what am i doing. When i played with my sister i always wanted to reverse role of being girl. Counted myself as girls in school like we have 15 boys and 14 girls + myself. Problem is i never thought it could be sign of being trans, but actually normal to everyone until i seen this sub and saw people with similar stories.