Hello pini85,
Welcome to the forum. It seems you are dealing with a few inter-related issues in your life: your appearance, your social status, lack of self confidence, negative thought patterns. You ask what kind of meditation you can do to help solve these problems.
I would not recommend a 10 day vipassana course whilst you have all of this going on. The courses are quite intensive and if your mind is deeply troubled since a long time you may have a strong abreaction (negative reaction) to the "pressure cooker" approach.
Meditation can help, especially with the negative thought patterns, with development of equanimity, and the development of acceptance. The types of meditation you have been undertaking (mantra and with music) can lead to a slightly calmer mind or mild sense of joy, yet are unlikely to lead to great change. It seems you might have realised they are not as effective as you hoped.
So where do you go from here: Well, as it happens you have already found the key through "Introduction to Mindfulness": breathing meditation.
In breathing meditation you are anchoring your attention to the physical sensations in the body as you breathe and you are calming the body with each in and out breath. The mind will chatter, you don't ignore it and you don't suppress it: you note/notice it. As your mind will
follow the body into a calm, awake, relaxed state the mind-chatter will diminish.
You will start to experience gaps in the never stopping thinking as you learn to ride this delicate balance of "relaxed but awake". You will start to see that you are not what you think - that thinking is a multifaceted process bubbling up from the subconscious and presenting itself to you as "me" in a 'fait-au complit'.
As you develop your "relaxed but awake" state you will start to find more equanimity/balance emerges naturally - as the light of awareness shone onto your thinking will bring the causes of the negative thinking to your conscious awareness.
You will start to realise that everything changes, that you cannot stop this (including ageing) - though you can take sensible measures to stay healthy.
You may find that as you worry less about how you appear, your appearance is less old! You probably have worry lines on your face from all this thinking that is troubling you, and of course, feeling the way you do now makes social interaction very hard.
The key to all of this is not to get goal oriented in your meditation or look for a "quick fix". It will take time practicing meditation to develop a calmer, more accepting view of yourself and the world. There is a meditation instruction called Shamatha/Calm Abiding if you scroll down on the
homepage that may help.
Really though the biggest answer to your "problems" is to realise they are created by expectation and this creates stress. Stress becomes quite habitual. So you need to learn to accept what is (it really doesn't matter how old you look - you
know this - but society tells you it does and you believe it ...).
I hope something there is helpful to you. Life is to be lived: you make it into a warzone for yourself instead at the moment it seems.
Kindly,
Matthew