D600 / Red Spot + Oil Spots????

My picture number 540 and I got the red spot (I hope it is the sun reflecting inside the lens?) and some dirt spots?

BTW: best KIT/Brand to clean the D600 sensor?

Is this normal?

I never got the red spot, even when I shot similar (sun behind) pictures, but never with a 24-85mm.

Could be the lens design?

Thanks in advance!
Ed