Was your dog not vaccinated against preventing Canine Lyme disease as a pup'?.
Lyme disease symptoms are;
Dogs will primarily show joint pain, perhaps fatigue and refusal to eat in early stages, further early symptoms include fever, lameness and muscle soreness, swollen glands and joints. They may cry when they move a certain way, or walk with a noticeable limp.
It can be difficult to recognise in a dog and can advance into late stage Lyme disease which will affect the heart. liver, kidneys, liver, eyes and nervous system and those signs can not usually be found until the dogs health is failing and blood tests are done.
It is important to take Your dog to the vet as soon as possible.
Usually with Lyme disease they seem to be tired and sometimes there joints are swollen and painful when touched .They can run a fever and be weak and not want to eat and have weight loss.To treat Lyme disease antibiotics are given for several weeks.There is also a vaccination for it.Good Luck and Take care