<s>[INST] I am 17 years old and I was on the depo shot i ended the depo shot inOctober due to gaining weight. I had a period for four weeks straight i ended on September 2nd. It is now Dec 1st and I havent had a period. My boobs are getting bigger and are super tender same with my nipples. I have heartburn all the time and I have noticed a lot of changes so I took a a home pregnancy test and it said Negative? I have all the symptoms could I be pregnant? [/INST] Hi, Usually the effect of the injection lasts for 3-4 months. The effect can last longer because the microcrystals of depot injection sometimes dissolve very slowly. Therefore, the period can be delayed up to 6-7 months. The symptoms you have mentioned can be due to the progesterone effect of injection too. To clarify things take a blood pregnancy test as it is more sensitive than home pregnancy test.  If it is negative don't worry. Start using barrier method of contraception until you start your period. I hope I have answered your concerns. If you have any other concern, do contact me through Chat Doctor. </s>