Giving a dog Vyvanse is animal cruelty. I'm calling PETA!
Seriously, we know it's you, anyone monitoring this forum knows it's you, unless you're very savvy with security, even then there's ways to figure you out, but we're mostly not worth LEs time. That's why we don't use useless things like SWIM, and other "anonymous" shit here.
To answer your ? Youwill likely be feeling the effects of d-amphetamine for ten - fourteen hours post the second dose. 150-mg is A LOT for anyone with low stimulant tolerance. Remember, full effects may not be felt until after two hours or more. Redosing this cmpd just doesn't work like with other traditional stimulants. Best too take entire dose for the day in one take.
I do not recommend doses above 60 -70mg/day, but am aware the some drs prescribe more. That is their decision, I feel it's too much, but maybe some people with legitimate needs require more. For rec use keep doses as small as possible and as infrequent as possible to avoid eventual tolerance build up.
Getting into stims for rec purposes can lead to very bad things.