My (Sort of) First Map - World of Tellus

[Seleucus I]

Your maps is generally looking good, but you have a few river violations. See here for more details. The biggest problem I noticed with this was that the central sea / lake has 3 rivers flowing out from it, it should only have one. Also, several of your rivers fork down stream which can't happen: tributaries may flow into larger rivers, but smaller rivers don't split off from larger ones.
I'm not a huge fan of the font you've used, but that's a personal choice.
Otherwise, like I said, looking good. I like the color scheme and background texture you've chosen; they go together really well. You've also done a god job with the positioning of your labels, and the compass rose you've added in goes very well with the rest of the map.