Running and Body Pump

I have been a runner for the last 8 years. I used to be a swimmer (from age 7 to 20) and had the swimmer body but I looked "puffy" and not muscular. I started running and stopped swimming to slim down. When I swam in college we did A LOT of weight lifting. I went from a bulky 135 to 117 (I am 5'2). I still have body fat that I would like to get rid of so I added strength training to my routine. I find that every time I add weight lifting to my routine I start to look "puffy" again. I think this is because I gain muscle very easily and I have short arms? I have recently tried body pump (for about 3 weeks, twice a week) and have found that I can not run as far or as fast because my legs are tired. I think this is because of the squats and lunges. For example, I usually run anywhere between 7 and 8.5 min mile depending on the distance and type of speed work. My fastest half is 1:45. For the past week I have been averaging 9 min miles and can barely make 4 miles! Is this because of body pump? I try to run 6 days a week.

I also do yoga, which I love. I am considering stopping weight lifting and only doing yoga and running. But I want to lose body fat so I don't know what to do! Any suggestions would be great! Also, I average about 1500 calories a day (average day: fiber bar and egg whites, salads, boca vegan burger, bagel thin, frozen veggies, dark chocolate, pretzels, red wine) Thanks for any advice you can give!