Well i do understand your concern and i assure you that you will be fine and you should not be worried.
Your urine infection is most likely cured from the antibiotic and now you are safe.
Regarding early bleeding while on the pill i do think that antibiotics may interfere with the working of the pill and may make it less effective.
Probably hormone fluctuations may cause early period and this should not be a problem.
I hope this helps
If urine infection is not treated with antibiotics it can result in sepsis.But since you all already treated you should be safe.