Ttc after tubal ligation

Could i be pregnant with my tubes tied i got my tubes tied 2 years ago after my 3rd baby and everything was going ok afterwards but then i haven't had a period for 2 months and usually regular this is my first time missing a period since i had it done and i feel very pregnant just like with my other three children all the signs and symptoms are the same nausea fatigue gas bloating constipation sore boobs and everything I really want to have another baby could I be pregnant I took a test and it came back negative what should I do can someone please help me