How should I feel about my girlfriend having lunch with her male friend?

Me and my girlfriend have been dating for about 2 1/2 months now and have been spending quite some time together.I love her dearly and she feels the same to my understanding. Last night I let her know that k will have my son today and will not be able to spend time with her, so I asked what her plans were and she said she was taking a friend out to get sushi that happens to be a male. Now for the record I'm not a a controlling person nor do I want to be, I just fell extremely hard for this girl. I expressed to her that I felt uncomfortable about this lunch get together and she showed sensitivities toward the situation and asked would I feel better if I met him first or if she didn't go at all. I really do not want to put a strain on our relationship by telling her id rather her not.. But I'd feel very uncomfortable if she did. I know opinions will not change the course on how I feel inside , but it will make my decision on what I want to say alot easier. Thanks

it's your girl friend so she will understand if you say not to go..just ask her nicely..:)