My baby has always been great at latching. We have had fairly little problems with our breastfeeding journey but lately I have noticed she seems to be latching very shallow and its pinching my nipples. A lot of the time I dont notice until she starts to pull off and it's because shes sucking directly on my nipple and sometimes feels like shes guming it

I pull her off as soon as I notice and will try to introduce my boob again for a better latch and sometimes she will latch properly, sometimes she does it again and I just put my boob away because it seems like shes just more or less playing with my nipple and it hurts.

Is this common for a 4 month old? Signs of teething? Maybe a phase?

Thanks!