Any tip?

I need some help when me and my boyfriend have sex I feel like my ph get unbalanced I always feel like I’m having a yeast infection my vagina just feel off and also my boyfriend penis is really long and thick he is beyond average but when we have sex it hurt me my vagina feel sore and I feel like I’m tearing. Do you guys have any tips or suggestions or products for both of us?

Also he is not circumcised, he washes it is there anything he can use to help with my ph, also he is not cheating. I also talk to him about it, also I’ve been to the gynecologist and my lab is in normal range.