What to expect ???

Ale
So Two days ago I took my IUD out because it was giving me many problems ... And I decided to switch to the pill.. I have taken one pill so far and I'm bleeding already 😳 its that normal ? I thought I wasn't gonna really have the side effects like you do when you first go on BC since I had the IUD already.. 
Any suggestions about the pill .. And or in general when it comes to sex, caution, pill problems etc 😬