C182 Pilot reported receiving no airspeed indications as well as the side cockpit window opening during climb out. Due to the lack of airspeed indications a runaway trim situation developed and the pilot immediately returned to land where it was discovered there was an insect in the pitot tube.

Narrative

After lubricating the hinges; pulleys; etc on my airplane; we went for a checkout flight prior to going to ZZZ in a couple days. Upon takeoff; the pilot's side window came open; I waited until we were at a safe height to close the window (aviate first); then noticed I had no airspeed indication so we leveled out and planned to turn around and go back to the airport. Upon turning right the aircraft pitched up strongly and the trim would not move. I forcefully pushed the yoke forward with both hand to continue level flight; I called Tower and since winds were 160 at 12 knots; requested the closed Runway XX. Tower indicated it was closed but there was no way that I was going to try to land with that kind of extreme back pressure and fight a 12 knot crosswind and since I'm based at this airport I know Runway XX's condition so I insisted on Runway XX. I landed successfully and put the aircraft back in the hanger. We contacted our Mechanic. We found the remains of a bug in the pitot tube which was the cause of the zero airspeed. The Mechanic felt that the new autopilot caused the Runaway Trim because of the zero airspeed and we have since marked the Autopilot Circuit Breakers in case this happens again. We updated to the latest software as well. We have flown the aircraft since and everything works as it should. The above times are approximate.