I need to change FOREVER!

     So its Tuesday and I'm feeling kinda yucky today!  My tummy kinda hurts!  It was a pretty crazy weekend.  We had a birthday party for my 2 daughters and my nephew.  Talk about food!  I didn't do that well but I didn't do horrible either.  I ate way more then I should have!  But less then I would have in the past!  Didn't gain any weight on sat but Monday morning was up 2lbs.  Today I was back to where I was last week.  I have been back and forth with the same 4 or 5 lbs for the last 2 months!  What does that mean?  I'm getting nowhere!  So I decided I definitely need to make some major changes in my eating if I am going to get anywhere!! I am continuing to work out with weights but need to add some cardio also.  HELP!  Where do I begin?  Ive never really counted calories!  I did pretty well with low carb but I don't know which way to go?