every time you have a problem you will resolve that problem. More learning takes place diving that in any class room.
I've really come to enjoy the dives that don't go perfectly, but are still done safely and without excess risk. I like to think of them as free learning opportunities; exposure to a bit of diving stress without the consequences of an actual emergency or serious error. I'm with you - I learn more from those dives than anything else.
To the OP - a Fundies class may be a hair overkill at this point (I am a GUE T1 diver and have assisted with numerous Fundies courses), and you're unlikely to do well in the course until you get a few of the new diver jitters out of your system. Unless money is no object, I'd recommend instead just spending more time in the water. $1300 in combined tuition (+ the inevitable gear changes) buys an awful lot of tank fills and spring entry fees. Fix the gear issues first (your alternate not working, tank position, wetsuit not fitting correctly), and find dive sites that keep things super simple. If navigation is a challenge - don't dive a site that requires anything more than rudimentary navigation skills. Find a site that has good visibility and easy access. Keep it shallow (20-30') for these first few dives after OW - not because you can't dive deeper, but because there's no real reason to. And the increased ambient light / longer bottom times / shorter surface intervals is a nice thing.
Here's an idea from my limited Florida experience - If Ginnie Springs is close to you, grab a couple of tanks and hit the basin with your buddy. The basin is <20' deep, crystal clear and warm, and it's near impossible to get lost (especially if the barrier is up). With the stairs/benches it's very easy to get in/out of the water there, and if there are any gear issues that need to be addressed, it's trivial to get back out and make the adjustments. Do your dive plan, review signals you're going to use during the dive (but don't get carried away), then spend 15-20 minutes making a couple of laps around the basin. Occasionally cut across and notice how your buoyancy changes when you get deeper and come back up. Surface, discuss, and do again. By time you're swapping over to the second tank, you'll likely be feeling a lot more comfortable in the water together. When you can easily and comfortably do that dive, with good buoyancy control, move on to something else.
For the next dives, find a different site with slightly more challenging conditions and do the same thing again. Blue Grotto would be an ideal candidate. Take advantage of the easy natural navigation... it's basically downhill/uphill. You can do a bunch of dives here as you get more comfortable by extending the bottom time and/or depth. Make a dive plan and stick to it - pay special attention to however you calculate no-deco time and gas supply and use this time to build good dive planning habits. When this gets old, go back to Ginnie and check out the Ballroom, or go visit Mother Ocean.
Be easy on yourself for the first dozen dives or so, then find some additional training when you realize you've fallen in love with diving. Fundies is a great course and would serve you well over a lifetime of diving, but at a minimum seek AOW/Rescue/Nitrox from a solid instructor.
My $.02... it's an awful lot of fun being a new diver; best to get comfortable and settle in for the long haul. =)
-B