ummmmm....feeling like I have to take a dump??!!!!

So 38 weeks and three days pregnant here, hubby and I had been laying off the sex for about a month or so which I felt bad about lol but today we decided to give it a go since I had my check up today and I was told I'm not even dilated🙄 Now, In the past with this pregnancy and I'm sure everyone who has sex gets swollen down there right after which I hate the feeling of but ever since after sex today I've had this pressure sort of feeling like if I have to poop!! I sit on the toilet and I feel like I have to take a huge dump but nothing comes out?! And even sitting causes discomfort...anyone have this problem after sex at this stage?? And or does it mean the baby went lower? Or what because I'm freaking out and I'm like omg we should've just not done it😳 but it's too late because the feeling is there and it doesn't feel great!! I can barley walk lol??? I'm so confused help me