separation anxiety?

i am hoping hunter isn't suffering from separation anxiety. ever since he was 6 weeks old he has been in the nursery and does just fine. the past 2 sunday's at church he has screamed his head off in the nursery. we have a night service that ends a bit past his bedtime which contributes to the fussiness. the first bad sunday he cried for about 20 minutes towards the end of the service. last night, he cried for about 45 minutes and they finally came and got me. it is so unlike him. normally he is very chill and doesn't mind other people holding him or watching him.

all of a sudden, hunter has now begun to prefer mommy so much. yes, it makes me feel good. but, what do i do when he screams in the nursery? i mean, i can't make the volunteers deal with his crying for an hour and a half. not to mention, it is so loud that all the other kids and classrooms have to deal with the noise. if the volunteers continue to come and get me during the service hunter will recognize the pattern and continue to cry so he can get mommy. i also help out with the service and often may not be able to get him (he is my priority, though!). what to do? i am thinking that maybe if i work in the nursery a few nights, he might get over this? or, do i just let him start out in the nursery and hope that he does okay and if not, have them come get me in hopes of him growing out of this?

who knows, maybe this won't happen again, but i am afraid that is just wishful thinking. so, all you moms out there that have had a similar problem, fill me in! thanks!