Brief Answer:
not to worry, please see the detailed answer below...

Detailed Answer:
Hello and Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concern...

Well, at this outset, this could be due to some hormonal changes(Estrogen and Progesterone mainly)...changes in the usual practice or even due to excessive stress or attention...our bodies functioning status is always dynamic since it's just happened for the past three times, I wouldn't be too worried about this.

However, there are certain things that can be done to overcome this...

Perhaps use some water-soluble jelly while having sex as well as plenty of foreplay beforehand and observe afterwards...

Additionally, a few relaxation methods like daily meditation/yoga for about half an hour, deep breathing exercises will help...

Sometimes, the usual surroundings and daily life can itself be the culprit. In that case, even a few days break, going out together for simple outdoor activities like movies, theatre, shopping, dinner, retreat can act wonder...

Let me know if I can assist you further.

Take Care
Kind Regards

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