Hi, welcome to HCM
there are very less that is 0.1%chances of getting pregnant even after IUd.
Very scanty bleeding can be because of vaginal infection
as well as cause of bloating
This bloating can be the effect of progestrone
Please have a urine pregnancy
test after 1 week of your period that is on 1st october.
You can contact after that.
Dont warry it will subside with out treatment.