AlmightyApkallu
Contributor
I am glad you had a great instructor but I don't think it matters what kind of instructor you had if you didn't dive in the ocean. The ocean (especially colder water like CA. coastline) is a different beast no matter what. I did most of my first 500 dives in the comfort of warm tropical waters experiencing many different conditions and challenges before I ventured out into So Cal waters. The first time I did a cold water ocean dive (granted it was in a dry suit) I felt completely out of my comfort zone. Between the temp, surge, limited viz, and kelp it was all a little bit overwhelming. I would highly recommend getting a guide or instructor to take you out. Maybe pursue an AOW card so you can become graceful creatures in addition to cautious and proficient.
I'm sure the Ocean is a different animal. This is specifically why I came here (and am beginning to regret doing so) to find the best route at not going it alone. When it comes to cold water, the lake we dive here is usually in the low to high 50's. I've been diving at 90 feet when the temp was 51 degrees in a 7mm and wasn't too bothered by it. Both me and my girlfriend learned and were certified when the water was extremely cold. We have also been diving in the summer when the visibility drops down to about 1~2 feet and were actually able to navigate to and find points of interest. Again, I know this doesn't mean we are ready to dive into the pacific but we are also not just some rich couple who got certified on some tropical vacation.
I would love to find a dive shop where I could have some one take us out and show us the ropes. I've heard of places, DM's and instructors who will do this, take you on a bit of a guided dive. It would be well worth the investment and I wouldn't have to be self conscious about us slowing anyone down. We plan on not only getting our AOW's but many other certifications as well.