Worried mom..not really baby related.

I need some opinions on this..today my husband and i are having a fence installed around our backyard. The guy got a pretty good look inside when he first showed up cuz i also have to keep an eye on my 2 year old while talking to him..then later i see him walking in the backyard and eyeballing our back porch (we have a grill and other items there). Well i just went outside to tell him to knock instead of use the doorbell if he needed anything cuz my son is sleeping, and he asks if we have dogs or anything...i immediately had red flags go up in my head thinking this guy is plotting something. I told him no but as soon add the fence goes up we will (which is a lie)..and even tho we'll have locks on the gate and have an alarm system..I'm totally freaked that this guy is gonna try to rob us later. I'm due to have baby #2 in 11 days and I'm a stay at home mom..so you think I'm overreacting? He made me pretty uncomfortable.