The first day of my last period was January 30th and I need to know what day I got pregnant

We can't answer that for sure. Most women ovulate 14-17 days after the beginning of their period but there is no way to tell you if you did or not.

Have you had an ultrasound? When did you find out you were pregnant?

According to my Gestation Wheel (the same one your doctor uses), if your LMP was January 30th, you most likely conceived on or around February 14 or 15. Now, please understand that this is not an exact science. If you are curious about paternity, you will have to have a DNA test done.