I would seriously go and do some circuits with an instructor.
However, I teach to 'rotate' if you like at 65knots. By this I mean apply positive back pressure to lift the aircraft off the runway in order to set a climbing attitude. This 'attitude' is where the nose of the aircraft partially obscures the horizon. When established in the climb with this 'climbing attitude' trim the aircraft. Without even looking at the ASI this will give you a best rate of climb speed of 75knots.
Approach
Try approach at 75kts until last mile / 300 ft alt, then lower last stage of flap
I would be careful configuring the aircraft 300ft above the ground.
Concentration should be on flying the correct flight path and at the correct speed, not configuring the aircraft so close to the ground. What if you get assymetric flap deployment? Can you handle that 300ft above the ground? What if you inadvertently balloon? You then have an upset to your flight path coming into land. Great if you have a 13000ft runway but maybe not on a 500m grass strip.
Also, are you leaning the mixture for takeoff?
Does the checklist tell you, you can lean the mixture for take off? Does the POH tell you to lean the mixture for take off? By how much and for how long? Doesn't fuel have a cooling effect?
When hot and high in a normally aspirated engine, your performance is gonna be pretty reduced. You therefore have to watch your airspeed and give your engine plenty of TLC !!
If you have doubts its got to be worth having an hour with an instructor ??