If it is difficult to get the the hairdressers, this is still not a reason to colour your own hair. You will never be able to achieve a professional result and it will be obvious that you have coloured your own hair, rather than going to a professional. This is because a professional will be able to spread the colour evenly throughout your hair. They will also be able to apply the colour for the exact amount of time needed for it to develop in different areas. For example, if your roots are a different colour to the rest of your hair, they will apply colour to them and let it develop for a very specific amount of time – different to the lengths where the shade may be different.
Even if you have roots showing through and you feel like your hair is in desperate need of a new colour, it is always worth waiting until you can visit a hair salon and see your hairdresser.