Help!! Boyfriend's mom walked in on us?

We have a very complicated relationship, and he's not officially my boyfriend right now but we are seeing eachother. His mom used to LOVE me, like absolutely love me untill she found out that I smoke weed, but I don't do any of that stuff anymore. Last night he snuck me into his house with a few other friends and at 2:00am everyone left, and my friend was on his way to come pick me up. My boyfriend's mom came downstairs and saw us, it was soo awkward. She came downstairs about 20 minutes later right when I was giving him a ********. What do I do? I don't think ill be able to see him anymore because of this, im so embarrased.