Age 14....oily skin and big pores!?

My face tends to get oily after a couple of hours of washing. I use blotting papers regularly but I want my face to stay matte for a long time! I use oil free moisturiser on my skin then apply loose powder on my face, hoping it would help stay less oily (i don't want to use compact powder because I don't want people to know I'm wearing makeup and I don't want it to appear cakey and clog my pores). Pores on my nose and the area around my nose are very big (well pretty noticeable). Large pores make me feel unconfident so that's why I use a concealer. I want a product that could help reduce the appearance or something. I heard that Estee Lauder has a good one but its way too pricey! Please recommend a product that would help oily skin (like powder, but no foundation or bb cream please) and large pores. Thank you!