She has them, so do male dogs (there are very few male mammals without teats, rats are one of the only species where this occurs). They do become more apparent with pregnancy
pregnant dog
They Pregnant Nuh BLOODCLAAAT !
yes this does mean she is pregnant after awhile the milk will come out if you squeeze the teats
yes.
The teats should not be swelling at all after being spayed unless they were swollen before the surgery. You need to take your dog in to be checked out by your Veterinarian as soon as possible.
No
She will gain weight and get swollen teats.
That would be quite unusual. It's likely that the dog does have teats but if she has not been bred they are very small. If you look closely you should see some indication of teats along their underside.
She most likely is- you should take her to the vet and find out for sure
if the dot is black, it probably squirts kool-aid
NO
Like breed her? Female will usually only allow a male on her when she is in heat.