Did the two club swing and then went for the driver almost immediately.

Basically I am very new to golf.
After two and half months with the irons, I managed to consistently made contact with the ball, most of the time with a fade. Naturally, I progress to the driver and of course the wood. Little did it occur to me that it would be too strenuous for the back, afterall there were never any discomfort with the irons.
Two weeks has passed, the pain over the whole upper half of the back has gone except for a few localised area.
Is this a common injury to beginners and as severe? But then I see many weekend golfers would tee off with the driver from cold.
Nonetheless, for me, a hard lesson learned and experienced!
Thanks.