Hello I am 17 and I had 2 periods 4 years ago which were really heavy and then they stopped I've had scans and ultrasounds to see what's going on but they said I am fine down there it could be bacuse of my weight as I was classed really over weight so recently I have began to loose weight then this morning I woke up wne to the tiolet my wee was as normal but when I wiped myself there was a little bit of blood and some sticky blood as well what can it be could it be my periods are going to be starting again

It could very well be your weight. Being overweight or underweight can cause period issues.

Have you had your hormone levels, thyroid levels and sugar levels tested recently?