I live in Nz and I was bombing off the cliffs into the river I'm sure you will be fine lol :) just have a shower after so your skin doesn't go dry and you don't have sand in places you don't want it, usual care :)
I also live in California and I went to the beach multiple times. The last time I went to the beach I was 25 weeks (im currently 36 weeks) and I was still going in the water. The waves did hit me but I did turn my back just to be safe. But go ahead and enjoy the beach just be smart (:
I'd say its fine. Keep your back to the waves or be lower than them hitting you directly in the stomach. But I've never been hit by a wave that knocked the wind out of me, just knocked me into the water. I don't think you'll have to worry about a yeast infection. But I could be wrong. Maybe avoid sitting in the sand and just wash really good when you get home.