What does inbound into customs mean?

I placed an order on january 13th for a quantity of 30 Phentermine they are supposed to be shipping to me (California) from India.They made it to the U.S on the 15th, and have been inbounded into customs since the 16th and the website still says it's inbound into customs.Is there something wrong??The website i ordered the pills from says it will take 15-30 working days to get here, but is it normal for it to be in customs this long?It is already the 27th.If customs doesn't like whats in my package will they confiscate it?Or will I be able to get it back?