ehh it depends on quite a few things. like your tolerance, if you have food in your stomach or not, if the pill is
actually ADDERALL or an off/generic brand like Amphetamine Salts.
my own personal experience is an actual Adderall 30mg capsule. one half of the capsule orange and the other clear- with tiny orange balls inside. if i have eaten and pop one then it will only kinda work for a little while, 1-2 hours MAX. but if i pop another one once i feel the affects are wearing off, it will keep me up all night. but then again id take it around 9pm or so. if i havent eaten the affect of the first capsule will seem to work quite a bit longer. but my tolerance has built and it takes about two to keep my speed goin.
if you took one at 12:30pm, you'll most likely be able to sleep because each one only lasts about 6-8 hours. the whole feelin like your not speedin and just alert and focused could mean you might actually have the medical reason Adderall is meant for. or your body is too tired from lack of sleep and the Adderall just wont work as well compared to your body being rested (happened to me). also could be that just one isnt enough to give you that high *speeding* feeling, which could be if you've built a tolerance to it.
all in all taking one of the 15mg teva/barr tabs (which ive never heard of as Adderall) or the 60mg IR (also never heard of as Adderall)--> if those are ADDERALL maybe just different name and form, at 8am and 12:30pm- you should be able to sleep around your normal time to go to bed. just maybe no naps before then
i do have a lot of experience with Adderall and i know how they work plus all the side effects that it causes. so if you ever need anything else having to do with Adderall, let me know cuz ill be able to help quite a bit