platy fish pregnancy

hey i have 3 platies in my 60 litre tank along with other fish an a frog(i used to have two, but one of them died:'(....) anyway, two of the platies are male and there is one female, and i know that i should have 2-3 females per male but didn't know a thing about sexes and what i should do when i bought them. OK, i need to stop talking.... i think that the female is pregnant because her belly is really boxy and oversized. It's not too hard for her to get pregnant, when there are two males with her. I looked it up and i think its certain, but i want to be sure. attached are two pictures of her, and i would also like it if you made an estimation of how many of the four-five weeks are left, because i only got interested in their breeding two days ago, saw about pregnancy and then checked MY fish and saw the female, so i couldnt have known how many weeks have passed. there's also something weird: she tends to hide like the males do too, but she mainly swims around. does that mean something?
PS can you help me tell female from male angelfish?
here are the links for the pictures, couldnt upload them here, too large:
http://s1062.photobucket.com/albums/...t=DSC00215.jpg

http://s1062.photobucket.com/albums/...3DDSC00211.jpg
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2 male platies
1 female platy
2 angelfish (unknown sex)
1 male african clawed frog

yannis2307