Struggling to go from a 12g to a 10g with my lobes

I was able to go to a 12 from a 14 early November and I've been trying every few weeks since January to get to a 10 and it's like i can get the tip in but it won't go through. I don't force it because it hurts and i know you're not supposed to. What can I do? Is it normal to take this long with smaller sizes?