singing out of comfortable range.M/20y

i have been singing for awhile but only learned proper technique recently. my question is is it bad to push yourself to hit a higher note that you have not been able to hit (im refering to the highest note in dream on by arrowsmith) it is just one note to high out of my falseto but i find when i try to do it i feel like im straining my self should i give it a rest?