What lovely imput from Rohiniranjan!
I just want to say that what you describe are two things:
1. Catastrophising in combination with avoidant behaviour
2. Putting lots of pressure on youself.
#2 is antithetical to what you want to achieve because by saying "I cant do this, I cant do that," you are effectively accomplishing nothing. It would not matter so much if your accommplishments were realated to other people, because other people can find someone else to help them. But you are giving up on stuff that is super important to you and only your wellbeing: like meditation and diary writing, for example.
Not every one is born with athletic ability. Not everyone is born with a big nose. But everyone is born with a mind and anyone can meditate, they just need to be willing to try and try and try, practice and practice and practice. It is a shame if you give up on that.
As for #1. you sound like you have, what is known in the West as, obsessive compulsive disorder: where people are plagued by distressing thoughts and then feel a compulsion to behave in a certain way so that those thoughts do not hurt them more. As far as I understand, these thoughts may never go away completely. But you can definately gain control over them rather than them having control over you. Te way to defeat them is to stand up to them and show them that you dont care. It is easier said than done, I know, but, intrinsically, you are the one giving power to them. Without you, they have no actual power.
Meditation is simply an exercise by which you train your mind to acceptance, ignore peacefully the madness in this world. By training, you will be stronger than those thoughts as your brain adapts to a new way of working. The same as, first the bear is stronger than you, but then you train at the gym and become stronger than the bear.
In combination with meditation it is good to practice gratitude and positve thinking. So whenever you experince yourself falling down that spiral nagative thinking, think of how grateful you are today that your parents are alive and just stay with that feeling. Think about how grateful you are that you have drinking water, and stay with that thought. Etc. When you write a diary, if you decide to go back to that some day, try to write two things you are grateful for that day and any reflection on any improvement you may be seeing by trying to meditate and how this minimises those worthless horrible thoughts.
Dont expect a big change to happen overnight, but if you try to make a pact wth yourself to practice this for just a week, I promise you will start to see really positive changes. One step at a time. But you must be the person making that step because your health depends on your resilliance and your decisions.
Chamomile tea is really calming and soothing for anxiety and catastrophic thoughts. Surely drinking this tea is something you will be able to do. I'd love to hear how you get on with it.
Lastly, reading is really good for engaging the mind into the plot and away from what is bothering you. HOWEVER, it is not a good idea therefore to read stuff that may worry you. You should be reading fiction books about two people falling in love and their positive adventures. Have you read "the power of now," by Eckart Tolle? That is a really good short book you may like and it is available as a pdf online for free. I hope that you may give that a try too and let us know how you get on.
Best wishes brother, <3