Capital gains exemption

Hi, I'm in a confusing situation that I hope you can help me with. I just sold my house last month and I'm trying to figure out if I qualify for the $250k capital gains exemption for a single tax payer. Now I should qualify since I lived in this house for a decade. The situation here is my mom was in a nursing home and did a quitclaim deed with me to transfer the house. I've read that because of the quitclaim I would have to pay capital gains on what my mom paid for the house, but she inherited it from my grandmother. So it's all a little confusing. Does me being in the house a decade supersede this quitclaim issue? I should qualify for the exemption since I lived there over 2 years, correct?