Hello, my name is***** and I have over 20 years of experience as a veterinarian. I'm sorry to hear that your pup ate something he should not have.
If he's a big Pomeranian it may pass but if he just ate it, within the past 2-3 hours, it's worth trying to get him to vomit it back up.
You can give him 1 tablespoon of 3% hydrogen peroxide per 10 pounds of body weight mixed with bread chunks or ice cream (no more than 3 tablespoons even if he weighs more than 35 pounds).
Then take him outside and run him around to get the peroxide bubbling so he vomits.
If no vomiting in 10 minutes repeat the peroxide dose once.
If he vomits and seems to clear his stomach and be done I would check to see if the dime is present.
Once she finishes vomiting and empties his stomach to try and settle his stomach today you can give either:
1) Pepcid-ac (famotidine) at a dose of one half of a 10mg tablet per 10 to 20 pounds of body weight every 12 hours.
2) Prilosec (omeprazole) at a dose of one quarter of a 20mg tablet per 10 to 20 pounds of body weight every 24 hours.
These will reduce stomach acid and should help settle his stomach.
Then feed a homemade diet of 1/3 boiled, lean hamburger or boiled, white, skinless chicken, all fats and juices drained off the meat, and 2/3 boiled, plain, white rice.
If he doesn't vomit the coin back up add 2 tablespoons of canned pumpkin, (not pie filling, just pumpkin), to each meal for fiber to help push the remaining dime through.
If you don't have peroxide or you want the best chance of getting the dime out I recommend that you take him to an emergency clinic to induce vomiting.
If he doesn't vomit it back up or you choose not to take him to an emergency clinic still use the bland diet with pumpkin to try and get the coin to pass. At that point all you can do is watch her closely. If he starts vomiting, has a tense painful belly or refuses to eat or runs a fever (more than 103F rectally) then that can signify a blockage and he should be seen by a veterinarian immediately. Surgery may be needed at that point.
Please let me know if you have any further questions.