Yes I would say the brown tabby in the first photo is a male
The red tabby in the second photo is also male
And the tortie (red and black) in the third photo is a female
LoL! Poor upside down babies. My first litter, the 3 boys were very pronounced from day one, like your top one. The second litter, 2 pronounced, one less so. Give him a couple of days - at least! - he'll fill out! The last pic is a little blurry - but looks like a little tortie, so almost certainly a girl!
Torties are almost always females, but plenty of experienced breeders have got confused with kittens changing sex. It is usually clearer when they are 6-8 weeks old, if you don't get the chance to sex them as they are born.