WHAT DO I DO?? Weights or cardio first? 

What SHOULD YOU DO? Weights or Cardio first?
Listen, I know we all seem to thing we need to get in so much cardio, but YOU NEED TO BE DOING STRENGTH TRAINING, not after cardio but either before or on different days altogether!
YOU want to be doing whatever is hardest first, and weight training should be challenging! If you do a full on killer cardio workout and then try to lift some weights, you will not have the strength left to do it at the level which you are actually able to.
Hey Ladies, YOU WILL NOT GET BIG!! It takes A LOT of work to get big!
If you are just starting with weight training, yes you may see a very small increase in size or even weight initially, as YOU ARE GAINING MUSCLE..
But what happens? You start building lean muscle and that will help. you burn fat more efficiently!! Which means a tighter, more fit look to your body.
Please remember, I balanced diet and a caloric deficit plays a HUGE role if weight loss is your goal.
BUT DO NOT SKIP THE WEIGHTS!!