Is this a big FUT scar? (Photos)

The size of the donor area scar depends on how many grafts were taken and how well you heal among many other factors.  It will take several months to see how well it heals.

Scars of any type are at their worst 4-6 weeks after surgery.  The scar then starts to mature over the next 6-12 months.  It is too early to draw conclusions about the final appearance of the scar.That said, there is always scarring of some sort at the donor area of a hair transplant.  After an FUT (strip) procedure hair a centimeter long typically covers the scar.  After an FUE procedure, the scarring is more subtle and shorter hair will cover it. 

You do need to be patient and review the scar in several months time when it has had a chance to settle. 6 weeks is simply too early to determine and you need to review this in more like 6 months than 6 weeks. If you need to disguise the scar perhaps then an option would be to have some SMP to help camouflage this scar - its merely an option and something you could look into in the future but not quite yet.

No worries, lets the donor area to heal. It is too early (6 weeks PO) for being worried about your scar. It is normal the redness and swollen. I don't know if a trichophytic closure was part of the technique. The final wound healing process takes 10-12 months after the surgery. I will suggest you circular massage of the scar with 1-2 fingers for 3-5 minutes 1-2 times a day for several weeks. I have seen bad scars with donor strips or FUE technique (manual, robotic and motorized). Contact you surgeon about his input too. Be patient. Good luck.

I use SmartGraft so there is no visible scarring afterwards.  That line will not go away and you will need to grow your hair out to cover this.

At 6 weeks, it does appear to be an early scar. You should wait until 6 months when the scar matures to know if this is what you got. Some people widen scars by their nature, It can be treated with scalp micropigmentation.