Telling my supervisor

In February I signed up for a new project at work which is regarding a 1 and a half year grant.   Obviously I didn't know I was going to be pregnant.  Now I told him and I have an overwhelming amount of guilt for signing up for a work project and not being able to fulfil my tasks as I wanted to.  I was hoping this project can help me excel and move up in the company but now I feel that due to my pregnancy it will hurt me.  I feel so sad and truly understand this horrible biased that happens to pregnant women in the work place.  Any advice would help.