female or male

Hey, I bought my electric blue acara months ago what I tight was a female, but since thought it was a male but now I’m not too sure as it’s been showing breeding behaviour with my bigger male (I know both males can do this) but I’m not sure now..can anyone help? Thanksss

Finding it hard to determine weather my platy is pregnant, sick or over fed! Not even sure if it’s a male or female!! I have four other platties which aren’t nearly ad large as this one along with four tetras and a dwarf gourami in the tank I’ve had the platties just over a week Any help...