I got a little worry today, nervous, im breastfeeding how can it affect baby? Will he also be nervous now?

Anxiety will not be. Transmitted via milk. Severe anxiety can be transmitted by behavior and the tension u have when u hold the baby. Try to be relaxed; all the ga ga go go stuff is important; "maternal looping" or bonding deeply with the baby it most important. If this is ok, your fine. Even if you have the energy to fake it, which u will have 2 do at times, baby will be ok; if not sleeping, depressed, see doc.
Babies R sensitive. If you are nervous your baby can sense it & may sleep less & fuss more. You will not make the baby into a nervous adult, the effect is temporary & resolves as you become more relaxed. Parenting is hard.