Weight Loss Frustration

I am really frustrated with my weight loss right now.  Granted, I had a not so great weekend with Jerry being away and eating out with the kids, but I have been really good ever since we stopped doing the fat flush and I have only dropped about 5 lbs in a month.  I guess I should preface that loss by saying I am hovering at about a 5 lb loss and seem to lose and gain that same 5lbs. 

I don't know what I am doing wrong.  I track my calories on My Fitness Pal and make sure I am under my calorie goal everyday.  Sometimes I am under by 100-200 calories of my 1300 allottment.  I run everyday on my parents' treadmill using the couch to 5K app on my phone and am on week 4 day 3 and will be starting week 5 on Wednesday.  I have been really good about not eating sugar and I have dumped diet coke pretty much all together.  I try my hardest to get 64 oz of water everyday, and only fall short about 20 oz any given day.  We have switched to whole wheat bread and pasta where we can, and I try not to eat too many carbs.  I get two servings of fruit everyday and at least two servings of veggies.  So what the hell am I doing wrong?

I'm going to try to start taking some vitamin D since I read that that could help with weight loss.  I am also going to start putting benefiber in everything I drink since I seem to have a problem in the regularity department.  I know this summer I'm going to make a commitment to run in the morning before Jerry leaves for work and will do the 30 day shred at night, but I might just start that little bit of craziness next month if I get really desperate.  I guess I really need to buckle down right now and not even give myself one get away day like I have been, although I haven't been going too crazy with that either.  We shall see.