joining a club was a good suggestion. You have to meet some people that dive. Get to know them and trust them, do some easy dives with them, it takes doing it. Once you have done a few dives, you will feel better.
My mom got certified at 73 years old. She had lousy weather, and rough seas for her first skills session. It was canceled. They ended up doing her first one in a spring. That is a good way to go if you have any in your area.
Her first real dive was with me and my buddy, on the keys. The first one, again, had some weather and bad planning on the boat mates part. She panicked, my buddy escorted her back to the boat.
The second spot we went, she went in with me. She took a long time going down the rope, (clearing her ears) but I just stayed a bit ahead of her and waited. She finally made it and we had a good dive.
She admitted, she knew she had to go in the second time, or she would never dive. She did very good. You can do it too. Find someone skilled and patient. And dive regular.
Also on the floaty legs, I have seen divers wear ankle weights.
here is a pic of my mom, (I got artsy with it, using Adobe)