i was looking to buy my first pheromones and saw there was a double strength option, i wanted to get both instant shine and ammu but i was wondering if double strength would be too overwhelming for a newbie?
and was also wondering if i’d be better off getting shine double strength over ammu or vise versa
With your age, that would be both a bad idea and a waste of money.
Stick with the regular dose for now.
But of course, an adventurer is never afraid to try, right? 
For the sexuals (Ammo and TUTH), once you have found your sweet spot/effective dose - and if the number of sprays work out, then yes going up to double strength can be a useful economy and scent control measure but if you are a young guy, it is best to start with the 1x product first.
This is because our Androstenone output falls with age and a fit young guy will be putting-out a lot more of it compared to an older guy (fit or not) and younger women tend to react positively to smaller Androstenone doses rather than larger - but you do find exceptions!
For socials, things aren’t quite so clear-cut and yes,sometimes 2x can be good and still widely usable on a young guy, esp where IS is involved - You seldom use just one spray of that one! 
With pheros, less is often more.
All you need is 1 or 2 sprays every time.
moreover with 1x : suppose it didnt worked with 1 spray , u can increase the dose with 2 or more sprays.
with 2x/ 4x : suppose you felt 1 spray is too much for you, then you practically cant reduce the dose.
so better first command the normal dose, if you find your sweet spot, and 2x suits you then in next purchase you can
Don’t buy from Androtics Direct. They care about charging you, but not about actually delivering your products. You can contact them over and over, and all you’ll get is a “Oops, seems like no one can help you at this time”. Horrible, shady, irresponsible company.