Why does my belly feel hard as a rock? I think it might be cancer?

A couple of weeks ago, I noticed that my left side of my belly is hard as a fucking rock. I really don’t understand what is going on with me. I felt it and I thought oh it will go down. I tried ice pack and it didn’t work. I work out and I’m getting more fit bit I don’t understand why my stomach is hard as a rock. I’m getting terrified. When I lay down it’s so hard. It’s my lower left part of my belly. I take iron pills because my doctor told me I needed to take them. I haven’t been taking them and I should be. I’m going to the doctor Thursday and I’m so damn scared that I may have stomach or kidney cancer. Or even pancreatic cancer.
I looked it up and some people had cancer or other diseases. I work out, do my best to eat right and looking healthier so why am I having problems? I know I’ll have cramps during my period but why won’t my hard belly go away. My friend suggested I see a doctor because it might be life threatening and be an adult about it. So I made an appointment for Thursdays. I don’t wanna die! This has NEVER HAPPENED TO ME! Is it part of getting older? I’m only 29!

Why does my belly feel hard as a rock? I think it might be cancer?
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