I have not started my period for almost 4 months now. Lately, I have been gaining more weight (I eat and exercise good). I have also been having really really bad lower back pains. I have had to stop what I have been doing and they have bee nso bad that I have actually been knocked to the ground and have had my mom help me into the house. I will be sitting down not moving or anything and I have had really bad back pains. I have also been getting dizzy and nausous lately. It sometimes feels like the room is spinning, it doesn't happen that often maybe two or three times a week.

My question is this a sign of cancer or is this normal?

Go to the doctor you may have more frequent menses and endometriosis, fibroids… a huge list of things. Go see your OBGYN.

You do not mention how old you are.

Pregnancy and menopause are two conditions that need to be considered if the criteria indicates that.

Any condition in the pelvis can cause lower back pain. also kidney problems.

Have a gynae check-up it is good practice even if everything is normal.

Ovarian cancer is hard to detect early. there is often no symptoms or just mild symptoms until the disease is in an advanced stage.

Symptoms Include

Bloating, a feeling of fullness, gas
frequency of urine
gastric symptoms like Nausea, indigestion, constipation, diarrhea
Menstrual disorders, pain during intercourse

Fatigue, backaches.

If your symptoms lasts longer than 2-3 weeks have it checked out.

Scientists are studying ways to detect ovarian cancer before symptoms develop.

here are some links

Ovarian Cancer Symptoms
Pelvic pain, discomfort, pressure

Changes in bowel movements such as frequency, consistency

Frequent urination or feeling sudden urgency to urinate

Pain during sexual intercourse

Abdominal pain, swelling feeling full, or bloated

Fatigue that is persistent

Weight gain in the abdomen

Sudden weight gain or weight loss

Keep in mind that these ovarian cancer symptoms may be signs of another illness.

Please see your physician if you are experiencing these symptoms for a definitive diagnosis or further questions.