U can start buying now, u are already 7 months gone,I think is not too early to start, cos as a first time mom u av a lot of shopping to do,I started buying arnd 28 weeks also especially d hospital tins ,nd m 33 weeks now nd am still buying lil tins dat remain because m also a first time mom and i dnt know wot is wot,so pple remind me of somethings dat are important,so its better fr u to start now nd ask pple for d important tins u need to get,u can ask ur mom or friends dat are already mothers for help,so u won't forget important tins