Hi dear..wished to know whether you have missed your periods ? If yes, then you must perform a urine pregnancy test ( upt) by self at home..this would clear your doubts regarding pregnancy.. Only excessive gas formation as a symptom with no frequency of urination or nausea or breast heaviness etc and no missed periods rarely indicates pregnancy..so wait patiently for your next menses to arrive..till then avoid gassy foods, try to take small frequent meals, walk after meals,and tab rantac 1 tab twice a day would help.. In case you miss your menses then go for upt.. And do remember, as your mirena is removed now,so better take some alternative birth control measure..