hm... that is one of those that I'd say too young to tell with 100% certainty. however I think it is probably a male based on first pics, visually narrow head on the last one may be because it was not happy with you a lot and puffed up, mine used to do it when he was younger and then you are getting confused on sex, visual middle line is also indicator of female, but the frog is under 3", so it might be because it is too young still. coloring under arms is not indicator, males tend to have brighter color, but there are plenty of males without it and females with orange coloring. i say wait and be back in a while with more pics