Dear Nacho
positivity is the only way to achieve a free mind. The easiest way to think positively is NOT to think negatively. If your problems can't be solved at once then, after peaceful logical consideration, shelve them until a solution can be found. Don't make them worse by churning them over in your mind.
Remember it is YOUR mind and you are in control of it - NOBODY ELSE.
Try this - allow yourself 5 minutes and 5 minutes only, each day to think negatively, then put all these thoughts aside and start
to take control of your emotions and thoughts.
You can change the way you think. try to give yourself a break from thinking about anything negative. If you fail don't dwell on your failure, have another go, and again ,and again until positivity becomes part of you.
You might also be trying too hard, sometimes doing meditation or exercises with too much effort, or worrying about the length of time spent or even aiming for a practise at a certain time can sometimes have the opposite effect and your energy closes in on itself instead of expanding outwards.
Try just daydreaming - let yourself relax - don't try to be spiritual or anything else - give yourself a break, walk or sit outside , look at the trees or at the sky. The LESS effort you put into it will make it more effective.
Be kind to yourself.
On a final note - if you can't sort those cold sores buy a bottle of pure Clove Oil and dab a drop on the sores. It's cheap and it works as clove oil is an great anti virus.
Love and light
Faune