Med switch to Vyvanse input

I could not get my 30 Adderall time release. After a lot of attempts at finding some I had my doctor switch me to Vyvanse it’s more money but I just don’t have the desire to do the chaos every month. She put me on 40mg of it though and I don’t notice it helping. Does it take time? My doctor said it may not work like my Adderall and she’ll change the dose if I need. Just curious if anyone has experience. Does it take a hit to work?