Question about eating and training (newbie)

I still consider myself fairly new to the whole running world - I run 3 to 4 times a week - between 3 to 5 miles each workout.  I am almost 11 months out from VSG and have really been working hard to keep up the exercise.  However, I am a little discouraged and need some advice.  I am running with a group (been doing this for about 4 weeks now) and have still been losing fairly steadily.  However, the past 2 weeks I have gained - UGH! - and this is not acceptable in my brain.  One of the trainers in the group suggested maybe I need to up my calories and see if that will kick my system back in to lose mode.  I average/budget 1000 calories for the days I run and 850 for the days I don't.  She, of course, stated she is not an expert on VSG technical info but has said for the "normal" folks, if you don't "eat" what you burn, your body will go back into "store the fat" mode. 

I am running my first 10K this Saturday and feel like I've hit a brick wall this week... can't seem to get more than 4.5 miles without feeling like I could seriously just fall over on the course.  Is this from caloric intake?

Any advice from you veterans?  Should I be "eating" all my exercise calories? or any portion of them?

 My first suggestion is to go back to your nutritionist and discuss what they want you to be at given your increase exercise. I know that my NUT has told me that she would like me to be around 1200 calories a day on days I do not exercise and she wants me to increase to 1650 on days I do exercise. I am running similar miles, and I also bike heavily and started swimming as well. 

Again, you really should discuss with your surgery NUT or see a Sports NUT.

Jay

Something else to consider here is in that 4 weeks you could of put on some muscle density which on the scale would give weight gain, but it could be lean muscle mass too.

Do you have one of those scales that sends a electrical impluse though your feet which can tell you your percentage of bodyfat?  They are pretty cheap these days