Thanks for sharing your concern.
your history suggests that you have malaligned teeth, that is the reason why your teeth are not the way you wanted them to be.
yes,definitely it is not due to the eruption of third molars.it is due to discrepancy between the jaw size and tooth material.
it can be very well corrected.do not delay, as age is also an important factor in orthodontic treatment.
you need to visit an orthodontist and take an OPG x ray
.after taking that he can explain you about your facial profile and based upon that how much correction is possible.
most of the times the teeth gets aligned by braces only, but in very rare cases jaw surgery
is also carried out to correct the malaligned teeth and the jaw.
your smile will automatically get corrected after ortho treatment once the teeth take their new positions.
hope this helps.
for further query contact me through my profile.