welcome man! honestly, constructive criticism is hard to come by here. the only thing i really find is people just building you up, and encouraging you to make better more detailed nice posts. but for this being your first its amazing! and the bottom picture is pretty awesome. i look foreword to seeing more from you, all of my pictures are from my phone also (i just bought a galaxy s8) so i hope i get some way better pictures soon! but this is a fantastic place to start. i hope that you get some good money from a post or two and get yourself a fantastic professional camera if its something you really enjoy doing! just dont give up! its difficult to grow, but hang in there! you'll crush it buddy!