As it happens localised scleroderma can cause symptoms outside of just skin involvement, in 2003 a large multinational study found that 25% of people with localised scleroderma had at least one other non cutaneous (non skin) symptoms, such as osteoarticular (affecting bones and joints), neurological (epilepsy, headache, peripheral neuropathy), vascular, gastrointestinal (heartburn), respiratory, cardiac, or renal. Less than 4% of those with morphea had more than two non cutaneous symptoms and none of the people in the study developed systemic scleroderma during follow up.
If you have morphea, it can burn itself out, even without treatment, within 3 to 5 years but of course the fact that it can doesn't mean it will. I have morphea and bullous morphea and 7 years on it's going nowhere but then I also have systemic so maybe that's keeping it going. Who knows with this disease!
The best thing is to be treated by a scleroderma expert so you can be sure of your diagnosis and treatment.
Take care and keep posting.