Pregnancy and vyvanse

I have been taking ADD/ADHD medicine for over 10 years. As soon as I found out I was pregnant I stopped taking it right away. Now I am struggling so much to get anything done. I'm a teacher and have so many things to juggle. Vyvanse has  helped me tremendously. Are there any alternative energy boosters or stimulants that I can take that are safe? I've been off it for 6 weeks but it's SO HARD!