Ahm not a smart man!
You can go to the other race’s starter areas (there are portals in Divinity’s Reach, or you should have one waypoint in each starter zone). Once you get a couple levels there, you can proceed through Kryta… It will also be helpful in map completion, too.
Are you sure you’ve completed every heart except for the one in the swamp area? There are 17 of them. If you have done all of the other 16, then maybe go do your level 10 personal story. That’ll give you some more exp. If you don’t want to do that, open your big map, and go to one of the other starter zones (Metrica Province, Caledon Forest, Plains of Ashford, or Wayfarer Foothills); everyone starts out with one waypoint in each of the starter zones.
Head south towards Kessex Hills, or take a way point to any of the other starter zones! Remember to stop and do events, collect resources and complete the story!
You can simply stay in Queensdale until you are strong enough to do the swamp area. All you need to do is complete a few events here and there and you should be leveled up in no time to be able to complete that whole map.
Do all of those vistas and poi’s as they all give nice exp. However if you do only manage to just scrape through this map. Before moving on to the second Human map you may want to take the advice of others above me. Go to each of the other race’s starting maps and complete them too before moving on.
I did this as well as all city maps for all of my alts and from memory by the time I hit the second map for the Human area I was more than high enough to complete it with no issues.
In fact I followed that same pattern for all of the other races maps. That is complete all the starter maps. Then complete all the second Tier maps for each race, third tier etc. Doing so keeps you above level for every map and makes them a breeze to do.
Good luck!