weights cause bulkiness

cedder1

I have managed over the past eight years to keep the 100 pounds I lost off. Over the last few months I have went from 128 lbs to 132-134 lbs. I absolutely cannot get back down to 128. I have tried everthing with my calorie intake. I currently teach cardio kickboxing classes 4 days a week. I am really good about mixing the classes up with exercise balls, weights, cardio, stairs, yoga and toning bands. The problem is that I appear to be bulking up (muscle). I know it is good to have muscle tone, and my clothes are fitting so I know it is not just fat gain. Is there any other women out there that seem to have a problem with this? I am 34 years old and have a height of 5'2". I currently wear between a 4-6 in clothing, but because of my height and muscle, I tend to look more solid than lean. Anyone have any ideas how to thin out but keep some muscle mass????