Some problems when making love (sex knowledge adult novel)

1. My girlfriend and I can have sex for more than 20 minutes. 20 minutes does not include foreplay, it is just the time of thrusting. This is too long. Every time she asks me to come out quickly. Sometimes she even says she is tired and asks me to stop first so that she can rest. Is 20 minutes really too long?
2. I want to give her oral sex to let her enjoy the feeling, but it seems that she is unwilling to do so. Once or twice, she said that she would give me oral sex, but after a while, she said no and wanted me to go inside. What is the reason? Is it because her place is too sensitive? Or does she feel that she doesn't like the feeling of oral sex?
3. When we make love, my penis gets wet easily. Is this bad? This should make it less painful when we make love, but my girlfriend always asks me why I get wet so easily. Of course, I love her, so this is normal, right?
I always wear a condom because I want my girlfriend to enjoy sex with me without worrying about pregnancy.
My girlfriend also gets wet easily. She gets wet every time we have sex. It's really great. I think this is also a sign that she is very comfortable.
I was thinking if my girlfriend didn't ask me to come quickly, I don't know how long I could last. I really want to wait a little longer to see what she would do. Haha, I was thinking, maybe my girlfriend doesn't like me giving her oral sex because she thinks it's unhygienic. She said there are always bacteria in the mouth. I want to ask, are there any girls who have this idea, so they don't let their boyfriends give you oral sex? If you have this idea, did your vagina feel itchy after oral sex before?
Girls, do you talk to your boyfriends when you make love? If your boyfriend asks you if you feel comfortable, will you answer? Sometimes when I ask her, she always tells me not to ask, and she will tell me if she feels uncomfortable.