Hello, I'm Dr. Deb.
I recently came online and see that your question hasn't been answered. I'm so sorry that you've had to wait for a response, but if you still need assistance, I'd like to help if I can.
I do have a few additional questions to ask first if you don't mind:
1.Do you think you could send me a picture of the lump? This LINK walks you through the process. If you can't send a picture, could you tell me how large it is?
2. Is the lump soft or hard?
3. Is is staying the same size, getting larger or getting smaller?
4. And, how old is your puppy?
Since it looks as if you are currently offline, there may be a delay after I receive your answer ssince I have to type up a response to you and I may be offline at the time you respond. But I'll get back to you as soon as I can since I'm on the computer some part of every day.
Thanks for your patience. Deb