Sounds as though the cockpit length is about right but very small changes can make a vast difference. Only done a couple of rides on my new bike and I had a similar problem accompanied with a bit of Butt Ache. Nose up just a fraction did help but I may have to Raise the bars by 1/2" and tilt the bars a bit more upwards. OR It may be lower the bars by a similar amount.

Trial and error (Without too much error hopefully) is going to correct it- but give the saddle time to adapt to your Butt. And just get the miles in.