Is my jack russell dog pregnant she was tied with a spaniel today and I have not noticed any sign ov bleeding before this incident, she had a litter ov jug puppies 4 months ago. Any help thank you. Dean

If she was willing my guess would be that she is in heat - perhaps early, perhaps late. I've NEVER known a female to permit being mounted unless/until she was "ready" or, of course, restrained (shades of Michael Vick).

Can I tell if she's pregnant? No.

You may have to wait and see, my guess is that yes, she was in heat.
Dogs average going into heat twice a year, depending on size and breed that could be more.
The heat cycle last about 3 weeks, she will not have bloody discharge that entire time.
It is ill advised to allow her to breed again so soon after giving birth.
You should seriously consider having her spayed.
How old is she?

I've actually known male dogs to "rape" female dogs, even those who aren't in heat or willing. It's kind of horrible.

Please spay your dog. We don't need anymore mutt puppies.

More accurately, she WAS in season, you just didn't see it. Not uncommon. There is such a thing as a 'silent' heat. Often, the first season goes unnoticed to the owner because it often isn't "typical". There are other signs that accompany a season beside visible bloody discharge... changes in eating habits, personality and activity, and things that many owners don't recognize simply because they are more subtle than dramatic.

Whelping a litter of pups in your home isn't easy, even though the dog does most of the work. Especially if you have never experienced it before. There most likely will be at least one unexpected veterinary visits, maybe several. And what to do with the pups... cute as they are, there is no shortage, and the law of supply and demand works quite well in these cases. Even though many people say they would like a cute pup, very few to none will desire one so badly that they will pay for one ahead of delivery, and frequently seem to disappear when the time comes to pick one up.

Have her spayed before she gets more than two to three weeks along. At this stage, there is minimal increase in difficulty or danger to the vet or the dog, and you avoid the decisions that invariably arise with unexpected, unwanted pet pregnancies.