So I actually have a question but don't want to start a new thread so thought I'd post in here, hoping someone can help me out?

I have a pretty sedentary lifestyle, uni student & desk job. I walk to uni which adds up to 2.5hrs walking per week, but other than that I have to rely on the gym for activity. (Can't walk to work cause it's literally 17km / 11miles each way & anyway my timetable wouldnt allow it because I start work shortly after finishing uni :P)
In the future I plan on having a stomach/back day but not for another 10-20lb lost or so.
Basically, all of my exercises involve dumbbells or machines. This is because of a few things, and won't be changing for the next wee while, but in the future I plan on doing body-only stuff like what Mark suggests.
My question/s is/are sort of vague, but am I doing too much cardio? I don't want to go to the gym more than 4 times a week. I feel like the cardio is necessary though because my basal metabolic rate isn't that high and with my sedentary lifestyle it's hard to burn calories any other way. I'm trying to make exercise more of my lifestyle e.g. asking friends to go for walks in the weekend etc but I'm basically at the maximum point for what I can incorporate into my daily life.
Secondly, the resistance exercises I'm doing... are they good for women? Lol I feel like that's a stupid question but honestly I get overwhelmed when I google various exercises and really don't know what ones would suit someone like me. I have picked these ones based on ease of technique because I'm not exactly a graceful swan and barbells and other more complicated things tend to leave me sore in not a good way. If anyone can offer some advice that'd be great. Keep in mind I'm a beginner and a female so honestly don't try and explain anything overly complicated because I'm too shy in a male-dominated gym to try anything fancy any way, as lame as that sounds. I am pondering having a PT session once a week mainly for technique and motivation, does that seem like a good idea?