Having read through some of your posts, I thought the following may help you to understand a bit more of the 'why am I felling like this?' and also understand that how you are feeling is a normal part of the quitting process.
Serotonin: This is the hormone that makes you feel good about yourself, makes you feel important. Serotonin is sometimes called the happiness hormone. It regulates the mood, prevents depression and makes you feel happy. Serotonin can be released by getting exposed to sunlight, by eating foods rich in carbohydrates and by exercising.
Endorphins: Endorphins are the chemical that can mask pain if we are injured and in danger - until we get to a safer place. This hormone can make you feel good, reduce your anxiety and your sensitivity to pain. Endorphins are released by exercising.
Dopamine: Dopamine is usually released when we know there is a reward on it's way - so most of you will recognise this when you know a 'smoking break' is on it's way Dopamine helps you to feel mentally alert. The lack of it might cause lack of attention, lack of concentration and bad moods. Dopamine can be released by eating foods that are rich in protein.
Oxytocin: This is like the 'hug drug' and is the feeling that you get when you are with those who you really feel at ease with.