Am I being petty?

My boyfriend went to uni (he's finished that now) and 1 of his uni friends has asked him down for his birthday (boyfriend will have to stay there as its 4 hours away) anyway the invite never extended to me (nor did it last year) we've been together nearly 3 years now and are buying are own place together. So I'm a little annoyed that the invite didn't extend to me (other girls will be at his fiends birthday), so I've said that if the boyfriend invites friends over when we live together I don't want this friend invited over (or staying) being as 2 years in a row I haven't been asked. Just wondering if that's being a bit too petty or not?
Also the house we are buying together I have put a bigger deposit down and will be paying the same amount of the mortgage (so technically I own more of the house)
Sorry for the long
Am I being petty?
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