I overcontributed to my 401K across 2 employments on accident. I cannot get a distribution before 4/18 so how do I know how much to pay and how to pay it?

I've already submitted my return in turbo tax with all the correct into (indicated an over contribution).  I do not see the penalty itemized on my return... so I am not confident that the taxes I own (per turbo) includes the penalty.  How do I know?