Pain when Dildo is inserted

I'm a virgin. But I've masturbated a lot so I'm wondering why I still get a slight pain when inserting my dildo. Once it gets past a certain point it's fine but it's super painful at first. My hymen is popped or ripped or whatever you want to say by the way. Yes I use lots and lots of lube. It's only for a second it hurts then I get past it. But it only hurts to insert and it feels like I'm pushing through a door or something cause after a certain spot it's easy