Could Fluoxetine Be The Cause For Severe Mood Swings?

Okay so i have depression i was on 20mg of fluoxetine at first it helped wonderfully, then i had to get onto another medication (and i am sorry i do not recall the name) but this medication was actually suppose to help me obtain a period..i am very irregular and i had to take ten pills for ten days, so a pill a day. Around mid way through of taking these pills i noticed a change in my hormones which i suspected normal, and i did end up being sexually active not safely..since then i have been moody i have been even worse in my depression and i noticed something very different with my body i feel a literal difference I m wondering if i am pregnant..i took two tests came back negative and i am also on a higher dose of fluoxetine would that have any effect on the tests. And before getting on any of these medications my doctor already tested to see if i could be pregnant it came back negative so i was in the clear but i think that one night after taking that other medication and spending the night with my bf may have gotten me pregnant but i have no clue i am sorry for a paragraph but i need help i need a clear answer, please.