Need advice...

Swannja1

Hey guys, I need some un-baby related advice. 

I invited some friends to join me to celebrate my birthday -its a milestone year. My email said something to the effect of "I'm going out to dinner at XYZ restaurant on such-n-such date to celebrate. Would love for you to join if you can." 

I tried to word the invite to make it informal, I didn't want it to seem like I was hosting a party or anything. Well, now I am second guessing whether I should be footing the bill for dinner for everyone. What do you think?

As a compromise I was thinking of buying a few bottles of wine for the table and (maybe) dessert for everyone. Or do you think I am stressing over a non-issue? 

Thanks!