First: Where was your position exactly? Your position IMO should have been cheating toward the 2nd base side of F6 and watching for that.. and HP could help on 3B or even 1B if needed.
Second: PU equally messed up, especially if he knew you were new and he were experienced.. but either way team work is best.. and the way to handle that is a nice quiet conference between you two AFTER the _Safe_ call.. you cant guess someone out, but you can meet up with your PARTNER, which is what he should have been, and discuss the play.
Dont beat yourself up too much, thats a very difficult play to cover in 2 man with runners on 1B and 2B... angle, hustle, and team work definately required..
That said.. perfection is expected the FIRST game and improvement every game thereafter
