Does Continuous Urge To Urinate After Intercourse Indicate Irritable Bladder?

Hi there, I believe I have an irritable bladder. Around 18hours after sex I feel like I need to wee all the time. My lower abdomen feels very sensitive, not painful but uncomfortable. When I do go to the toilet it still feels like I need to go even if there s nothing there and feels like my body is trying to wee when there s nothing there. It also happens when I dont drink enough during the day. Do you think this is an irritable bladder, if so what can I do? I saw a nurse who really didn t help, I didn t describe any symotoms to her because as soon as I said after sex she interrupted to say I should go to an sexual health clinic, but I know I don t have an sti. Thanks Grace