Welcome here Besos!
Congrats on getting back to the gym!
Surely you will take it a little slow at first after being away for 3 yrs ... not too intense to cause injury...gradually increasing your time & training level to accomodate your physical capabilities.
You did not list the 'diet' you're starting (?) Does it include 5-6 meals/snacks per day, lean proteins (chic, fish, eggs), complex carbs (veggies, yams, oatmeal), staying clear of processed (packaged) foods? This will get your new plan off to a great start... plenty of energy to train with...and do not leave out those healthy fats! It may help to think of it as a 'lifestyle change to healthy eating'... instead of a 'diet'.
If you have not cruised the women's board already for info, much is posted here on what gals eat & how they train to assist in reaching the goal we all strive for: a strong, lean, & fit body.
Xenedrine, Metabolife, etc...(so many ECA combo's out there)... are supplements that can assist in energy levels & enhance training. Before you decide to make these a part of your plan, please be familiar with their effects... and remember too they are 'supplements'... they 'supplement' clean & healthy nutrition with proper training practices. By changing whatever eating habits & inactivity have caused your recent weight gain, you already will go a long way toward making progress to a fitter & happier 'you'.
One more thing before leaving comments to the rest of the gals... have you set yourself a goal? Please do not be too hard on yourself for slipping from your active gym days...we are all 'under construction'. You will find lots of encouraging words & stories here to keep you motivated!
Flex