Stomach bloats after eating

I'm 21yrs old and about 2 months ago I began experiencing bloating and a hard stomach after I ate. I also had stomach pains but not always and have fatigue/brain fogginess. I suffered from constipation too and realised I have most of my life usually going 1-2 times a week. At one point I lost my appetite and barely ate in that week and then a week after I was hungry all the time no matter how much I ate. I still get all these symptoms but my appetite seems more normal at the moment. I am finally going to the docs next week but just wondering if anyone else is or has experienced anything similar?

Thanks :)