Q: I have been seeing someone for four months. He's only the second man I have ever made love to. Making love can be very intense, and there is a lot of passion between us. Lying in each other's arms afterward for what seems like forever is wonderful.

My question: What does it mean when a man pulls your hair and bites you while making love? The first time he pulled my hair, it scared me, but it doesn't anymore. When he bites, he doesn't hurt me, but I sometimes have a bruise afterward, like a hickey.

Honestly, the sex is amazing, and it seems like every time we're together, we make love. Also, do you think that it's possible to be in love already?

A: Are you sure he's not hurting you? It would seem like hair-pulling and biting would hurt. Maybe it hurts but not very much, and because you're falling in love you're willing to put up with it.

My question would be, does hurting you give him pleasure? And do you want to be with a man who likes to cause you pain? These days, because of the popularity of "Fifty Shades of Grey," certainly there are some couples who are engaging in a bit of S&M. So the question for you to decide is whether that's OK, and more important, is it something that's going to fade away, as it does in the book, or something that's going to escalate?

I think you two need to talk about this rather than just let it happen without knowing what direction this is all going in.

Q: I am 19 and have been dating my boyfriend for a while. I was a virgin waiting for the right guy, and he is it. I love him very much. School ended and we live far apart, so I will not get to see him much. He came to visit last weekend and we had sex for the first time (and second, third, fourth, etc.), and it was amazing. He gives me oral sex and always makes sure I finish. I want to return the favor to him, but I am afraid to. He has never asked me to, but I want to. Is this fear normal?

A: Let's take away the word "afraid" and substitute the word "nervous." A penis can't hurt you, so there's nothing to be afraid of, but trying anything new can make you nervous. But there are different kinds of nervousness. You're probably nervous right before a big test. But you also probably were nervous before you had sex for the first time, and yet you repeated the act over and over. So admit that you're nervous, but also tell yourself that making friends with his penis is going to be a wonderful experience.

I never tell anyone that they have to engage in any type of sex, including oral sex. But if you want to and all that's holding you back is a case of nerves, then just steel yourself. I predict that once you get started, your nervousness will go away and you'll be fine.

Q: I've been married for 20 years. We are in our early 40s and still love sex, but I am having trouble maintaining erections. I'm an insulin-dependent diabetic, and I think my disease is the main contributor. My doctor is giving me T injections twice a month. But is there is a legitimate natural supplement out there that may complement the injections in assisting erections? Or is Viagra the only solution?

A: I'm not a medical doctor, so I can't address your question, but let me say this: If your doctor can treat you in some way, including with Viagra, and you can have sex, then you should do it. I understand that life would be better if you didn't have diabetes and its attendant side effects, but you do, and so you have to deal with it. I certainly wish that I'd grown a few more inches, but I didn't, and I think you'll agree I've made the best of it. So keep looking for solutions, as I don't want you to give up, but don't look at a solution, like taking Viagra, as a problem, but rather as a wonderful tool — the way I look at step stools!

Q: I am 34. My first time having sex was a year ago. Since then I have had two sexual experiences, both in the past two weeks with an 18-year-old female. She enjoyed foreplay, but after I put on my condom and we started having sex, she stopped me. She told me I need an older woman to teach me. What can I do to get better? Finding an older woman is easier said than done.

A: It's hard for me to guess what you were doing wrong, assuming that you actually were having intercourse. But you don't need an older woman, just a woman who is more understanding. Since you didn't have sex until you were 33, I can safely assume that you also haven't been in a serious relationship. My advice is to find someone who will fall in love with you, and then no matter her age, the two of you can work out how to have sex that is most pleasing to both of you.

"Sex for Dummies" (IDG Books) is among Dr. Ruth Westheimer's most popular books. Have a question for Dr. Ruth? Write to her at drruth.com.