male or female? green bird

i've had this bird for around 2 and a half years and always thought it was a male. i saw my other male bird trying to mate with it and it never fought him off but i think he did peck him a little... (idk if it was mating or just him being in the mood) but now i don't know what to think lol. originally it had a pale color with small rings but the color has darkened and its like a light royal blue with the circles. please tell me its a guy, nobody has mated with it for multiple years and it hasn't ever had a brown female cere