RLC circuit and equivalent load resistance of a transformer
Impedance transformation

A transformer converts an impedance by using the turns ratio squared. Your formula just used the turns ratio (un-squared).

The reason is quite simple when you analyse 1 ohm on a secondary with 1 volt across it. This bit is easy; the current is 1 amp. Now, if the transformer primary had ten times the turns, the primary voltage would be of course 10 volts and the load current taken as seen on the primary side is 0.1 amps. Hence, 10 volts divided by 0.1 amps = 100 ohms. That's called the primary referred secondary load impedance.

A 1 ohm resistor is transformed to 100 ohms using a 10:1 transformer. 

Apart from the above, it is unclear if L7 took account of the primary magnetization inductance as would be seen when you connected the transformer in parallel with L8. In other words I couldn't check this because your values are unclear.

Q factor

If you want to check your Q formula, this wiki page on RLC circuits can help. If I read your circuit correctly (i.e. the charging resistor can be ignored when the switch operates), then your formula is correct.