Does a penis feel very different than a silicone dildo?

I'm a virgin and wanted to get used to penetration on my own (with a dildo) so that sex won't hurt the first time so I've been using an average sized (like 5 inches long and 1.5 inches in diameter) somewhat flexible silicon dildo... But I'm wondering how different a penis will be. Obviously one is made out of flesh instead of silicon, but I mean in terms of penetration/how dense/stiff/forgiving it is? When I'm turned on and use a bit of lube I don't have any problem inserting it, but the penetration doesn't usually feel THAT amazing and sometimes inserting the full length is a bit uncomfortable/I think maybe it's pushing up against my cervix... How does it compare to an actual penis?