I got Botox yesterday and have a line or vein sticking out above my eyebrow running up my forehead. Is this normal?

It is unlikely that this is related to your Botox treatment.  As others have suggested it is possible that it was present before the treatment but not noticed until now.  If it persists or is causing issues, return to your injector for an evaluation.

Thanks for the question! It isnt normal for botox to cause vein formation - but it would be too soon any case for the botox to be exerting any action. Was this definitely not there before? It might be worth checking old pictures to compare.  If it is an irritated vein, and new, if its not painful it should go back down int he coming days. If it is painful I would get some medical advice.

I agree while the vein was there prior to your injections it may not have been as noticeable.  Now that you are concentrating on that area- it seems more prominent.  It is not related to your botox and I hope that you will get great results.