It sounds like your thinking wheels are working overtime at the wrong time! Grounding into your body will alleviate this. Visualize that you're sending your thoughts down to your feet. This will have a grounding effect. Also, focus on where the pleasure is at, allowing yourself to get lost in it.
Make sure that you're addressing any hang ups with sex during pregnancy such as body image issues, negative messages, fears. Then acknowledge and accept any pleasurable sensations you are having and allow them to wash fully over you. Quiet the mind. Be fully in the moment!
Urinate ahead of time. Your G spot is likely feeling more alive during pregnancy, hence this feeling. You may also be a female ejaculator. This is NOT pee. If you squirt, enjoy it. It's a sign you're turned on!
The first time I ejaculated I almost had a panic attack. It feels so similar to the act of urinating, but it's not! Many mistake it for urine, but it's not. Female ejaculation can happen with or without orgasm, and usually involves pulses of liquid squirting out at the height of passion. Mine are usually associated with climax, not always.
It's expelled via the urethral canal by 40 or so glands and ducts of the female prostate. Research has analyzed it and while it contains traces of urine since it comes out of the urethra (just as your partner's ejaculate comes from HIS urethra), ejaculate actually contains glucose, fructose, and prostate-specific antigens. It's sweet, according to my personal feedback!
Women are likeliest to squirt with G spot stimulation. A lot of men find this reaction really hot, as long as they're reassured it's not pee. Ejaculation is a wonderful experience too few women are able to enjoy!
Pregnancy is beautiful! I loved being pregnant, too! You are still a beautiful woman. Approach your partner gently. He could be having some issues himself with his masculinity or with a bit of envy for the attention the kids get (you probably, understandably have less energy and time to devote to him).
The body image problem is a BIG one for all of us. First of all, try to stop judging your body and start appreciating the fact that it is a miraculous vehicle that carried your children and still carries them, that carries you through this life. Slow down and honor your body.
First, practice patience. You only gave birth 3 months ago. Birth is a traumatic event on the body. Women need time to recover in every way. If your partner doesn't understand that, let him know what you're experiencing (without attacking him), then suggest ways that he might be of help. At the same time, don't diminish the importance of sexual intimacy.
Always begin your conversations with your partner with an affirmation such as "I really love and miss..." or "I really would love to try..." Don't attack or accuse or you'll lose his attention. Be gentle. It's his ego at stake and we all know how fragile those are. At the same time, please be sure to include boundaries you're comfortable with in this conversation.
Second, are you taking care of yourself, giving yourself time to feel good in your skin with exercise, yoga, proper diet, self-care?
Third, literally talk to yourself in the mirror, thank your body for giving life to three human beings. It's amazing what you've just endured. Be humane to yourself. Don't self-talk yourself in a way that you wouldn't other women. In other words, can you imagine saying any of the things you're saying in your judgment of your body to another woman?
Can you see the beauty in the female form and appreciate the miracle of life in yourself? Breathing and being "in" the body is huge here. Feel the sensual nature that is inherent in your every cell by taking just a moment in the shower or even on the toilet if you can't escape to acknowledge the body in a reverent and appreciative way rather than a judgmental one.
Sexpectations put a lot of pressure on women during this time. You either need to be frank, stating what your needs are that don't involve sexual intimacy. You could also approach sex as "sexercise", as there are calories to be burned.