IUD pain

So women yesterday I got IUD (jaydess). It was not as painful as I thought it would be. Right after I started to feel really dizzy and nearly fainted . I probably stood up to fast. Through out the whole day I had the worst cramps and back pain ever. Normally I have terrible abdominal and back pain during the period. Also I have never had a child so I suppose It could be expected. Thank God my boyfriend was with me all the time. He made me food and tea, put me under blankets and watched cartoons with me. But what I want to know is how long before the pain goes away? And what to do to make it more bearable?