Questions... tell me if I’m being silly

My fiancé and I just had sex. After sex he pulls out and his cum is still in the tip, but it appears that there was gooey white at the base closest to him too. I didn’t think it was mine, but he says it was me since I’ve been having discharge and used a vibrator and all... I was worried that his cum moved up the condom on the inside but I couldn’t tell because of the lubricant of the condom. I have a hormonal IUD that I’ve had for 8 months now. I know it’s in place. Question is, was the white stuff mine or his? If his, should I be worried with the IUD?