It might be an upper respiratory infection (URI). Allie had that at about 9 weeks and the vet said it is very common in all breeds of kittens. Untreated it can cause some pretty serious damage. (He does clinics for feral cats and sees all sorts of terrible stuff) Allie got antibiotics and eye ointment for her URI. Kittens are due at 8 weeks for their first vet visit and vaccines so maybe if you call they can take yours early and address the runny eyes as well?
Although it sounds funny ( and I did laugh when my vet told me this!) kittens contract chlamydia and it settles in the eyes which cause them to water and get a green infection in them (eye boogers) that can easily be treated with oral antibiotics!!! But like said before...it to could be an upper respiratory problem..which can also be cured with antibiotics!!! Good luck!! Keep me posted!!