Pregnant with baby number 5. First time ive ever had any real complications.

I am expecting baby number 5 this time the ultrasound tech said that its finally a girl it makes me so happy I've always wanted a little girl. this is also the first time I've ever had any complication and it kind of scares me. I have low lying placenta and I've also had a really bad kidney infection they believe I am also having gallbladder problems. trying to stay positive don't want anything to happen to my little girl. Has anyone else experienced anything simular?