Question regarding new build

Hi guys,

Am in the process of building a new home my first so not very experienced in all this and have a question for all the building experts on this forum.

We are currently at frame stage, the frame is seemingly complete as well as the roof trusses and what not. Gutter and fascia are almost done and roof will go on at some stage this week.

My question relates to windows, having a walk through site today I’ve noticed that our window frames don’t look like they are completely secured to the frame of the house.
There is a three inch nail on both sides of the window frame that sticks out of the window frame by about 50 mil, and goes into the frame of the house however with a gap between the window frames and the house frames of about 50 mil.

Am I overthinking this or is this normal for this stage of the build and are they completely and properly fitted at a later stage?

Thanks everyone in advance for all the help!!