It's normal to feel these feelings. Don't be hard on yourself. We're here for you
There's nothing in your story that tells me you need chemo first. Let's wait for the bHCG to come in though. By the way, that slight LDH rise means nothing. It's normal.
I guess you mean that two more lymph nodes are slightly more than 1 "cm", not "mm". Even if that's the case, you can still proceed with RPLND, but the chances of requiring 2 x BEP after will be higher than before.