How did you go with your weigh in? I saw at the start of this thread that you have a big journey ahead of you. You should take a look at this guy
who has lost an incredible amount of weight - you may find some inspiration from his blog. Click across the slideshow of pictures to see his massive weight loss from a very big guy.
I'm not being nasty at all but the macaroni meal may not be the best meal for weight loss - regardless of points. You probably feel more full from the tuna because of the protein in it. Protein is known to make you feel fuller for longer vs. the other macronutrients (fats and carbs). At the end of the day you're still eating a mac and cheese packet which is very carb dense.
Please take this the right way because I want to help you. If you are having trouble with hunger then you need to eat more protein. You can increase your lean meat intake or maybe try a protein shake supplement. I have a book called 'The Power of Protein' by Chris Smith which is basically a recipe book for high protein low carb meals. To be honest the recipes in there are a bit gourmet for me but I still use it to come up with more basic recipes for myself. Maybe something like this could be beneficial.
Learning about losing weight is to be honest very difficult. It's hard to know what you can and can't do and what works for you. My best advice to you is to never give up. Keep trying and you will get there!