Last December I was also prescribed Doxycycline Hyclate 100mg for...

Last December I was also prescribed Doxycycline Hyclate 100mg for mild acne. I am 17. After a few weeks of taking it my acne appeared to have been getting better and I felt quite relieved. However, after about a month and a half of taking it, I woke up one morning with what felt like extreme heartburn. My stomach felt like there was a lump in it and in the middle of my chest where the esophagus and stomach connected, there was extreme pain whenever I swallowed anything. At first I thought this was just due to excessive acid in my stomach, but as it turned out it was the medicines reaction to a virus/cold I was getting -- the symptoms were nearly like an ulcer (which is what we initially thought). After stopping the medicine for about a month, I was fine and I started taking it again. Now it's been about the same duration of me taking it, and once again I feel as though I'm developing another case of what feels like extreme heartburn/an ulcer. Has anyone else had this problem?