Is it normal for your mole removal scar to have a lump under it?

Thank you so much for your question. I tell my patients that it is normal to feel a bump or firmness underneath the tissue where a lesion was excised. This can be present for even up to a year after surgery. As the scar matures over time, this firmness usually resolves on its own, and can be helped along with certain topical creams and scar massage techniques.
As far as the "inconclusive" pathology report, it is in your best interest to speak with your surgeon/dermatologist to determine a definitive diagnosis and what, if any, additional steps may need to be taken. 
Best of luck to you! 

It sounds like you might have some scar tissue developing where the mole used to be.  I recommend following up with your doc to make sure there is nothing else going on and then perhaps get an injection of corticosteroid medicine to decrease the scar tissue and decrease the bump.  
Hope this is helpful!
Dr. Amy