Do you think I have ADD?

Get in touch with a mental health professional as that will be the only way that you could definitely have a diagnosis of ADD. As it is affecting your every day life you should do so in as swift of a time as possible. It is not shameful to ask the help of someone who is in that profession but a sign of strength. Do not be afraid to ask as this might possibly be the best thing that you could do to take care of the problems that you are currently experiencing.