Dark phlegm. To 7 years now. iam 28?

You seem to be suffering from gingivitis, at the least, or even worse, periodontitis but the exact diagnosis can be established only after proper clinical evaluation of the case, where in the depth of the gum pockets and bone loss needs to be assessed. Both these are tentative suggestions based on the description that you have mentioned. But one thing is for sure that there are deposits called as calculus on your teeth which are causing the damage to the gums and causing bleeding while brushing or otherwise. These deposits cannot be removed by toothbrushing and need to be removed professionally by the dentist through a procedure called as scaling. After that a proper maintenance of daily plaque removal by meticulous tooth brushing will be required by you so that the results of the treatment can be maintained for a long time. You have already delayed this problem by ignoring the symptoms but it is high time that you search for a dentist as soon as possible and try to book an appointment for scaling without further delay before the symptoms aggravate further. You are definitely too young to be experiencing bone loss or losing a tooth because of their week Gum and bone support. Regards.