Like KSH says, it's probably not worth getting cycling shoes for two tri's a year, but if you love cycling and are on your bike several days a week, then cycling shoes/clipless pedals are _so_ nice. I would _never_ go back to not having them.
I think you have enough time, between now and Mother's Day, though, to get used to clipless pedals if you wanted to.
OTOH, you could do the first tri and ride your bike in your running shoes and have one less little thing to stress about in transition for your first time.
Still, I know it would stress me _more_ to try to ride in running shoes rather than worrying about one extra shoe change.
PS, you may get addicted!!!
Nanci
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"...I'm like the cycling version of the guy in Flowers for Algernon." Mike Magnuson