Slightly Underpitched or grossly Underpitched?

Hey everyone! I'm sure this question has been answered but I was unable to find it in my search. I brewed yesterday and was shooting for a 1.080, when to my surprise I hit a 1.090. I am totally ok with the fact that I may end up with a much bigger beer, but I made a starter for a 1.080. In Beersmith and on mr malty they say I'm about 20 billion cells short of a proper pitch. I know it's not the worst, but I also know it's not the best. I made a 1.5L starter with 1 vial of wlp002 and 1 vial of wlp007. That's two vials in ONE starter. Is there a straight answer? How stressed will that yeast be? I'm fermenting in the 70-72 range currently. Thanks for any feedback!

Unless you made a large batch (10 gallons +) you should be fine. Don't sweat it.
For a 5 gallon batch (unless it is a big beer) I always use 1 vial in my starters.

I think you'll be fine but am curious as to whether this was an extract or all grain batch?

Sounds ok if this is a 5-5.5 gal batch. Iv'e made a fine 5.0 gallons of 1.074 OG beer with only one dry yeast pack (11g) which is about the same as 2 liquid yeast vials with no starter.

underpitching by 20 billion cells isn't the end of the world. you were in the ballpark.

It'll be fine. No worries.

Thanks for the feedback everyone! I thought I would be alright but you know how it is. This is an all grain biab 4 gal batch.