A lot of tanks have healer alts. You're bound to run into one, like me, who knows when you're messing something up. We might try to offer you advice, though we know it's considered rude. Otherwise, if you feel like you are to blame for the wipes, or you really have no idea who is messing what up, just ask in the party chat, "Is there something I am doing wrong or missing?" Trolls will jump on this moment to attack you, but most people will offer any honest observations they know of to try and get you to see a detail you might be missing.

Don't let one run, or one of the harder dungeons get you down. Qarn was no joke when I was leveling my healer. Up to Qarn, it's all tank-and-spank and spam DPS. Then all-the-sudden, people actually have to pay attention. Chin up. You'll be fine