Hi JustGottabeme,
Welcome to the NeuroTalk Support Groups.

You really need to ask your prescribing doctor about this concern.

I just looked in Medline regarding potential side-effects from the Vyvanse and headaches are listed in there.
There is also a section in the "Special precautions" part regarding the heart.

Side effects
http://www.nlm.nih.gov/medlineplus/d...l#side-effects

Special precautions
http://www.nlm.nih.gov/medlineplus/d...ml#precautions

Were you on a high dose of the Sertraline before you weaned off and did you wean totally off before starting the Vyvanse.
The info. regarding Vyvanse says it should be started at a really low dose and gradually increased.

How should this medicine be used
http://www.nlm.nih.gov/medlineplus/d...07047.html#how

Many years ago I took quite a high dose of Sertraline/Zoloft for some OC issues and Anxiety.
I hated the way it made me feel and it didn't actually help me personally so I went off it.
I didn't wean fast enough and I became quite ill in fact.

I don't know anything about the Vyvanse I'm sorry except for what I have just read but I'm sure others who read here may.

I vaguely recall someone in the ADHD forum was talking about Vyvanse recently.
Perhaps asking there might be helpful as well.

I do know that for me, getting OFF the Sertraline was difficult and made me sick.

Let us know how you get on.