No period, bloating after meals, am I pregnant?

No judgment, please! I'm 15 years old & I AM still a virgin! However, I have done things such as handjobs, bjs, and been fingered. My periods have always been very irregular. My last one ended around the 19-20th of may. I haven't gotten one yet this month! Lately, after every meal I eat, I feel SO full. & as of recently, every time after I eat, I bloat like crazy! I took milk of mangesia the other day due to constipation, and the bloating went down significantly over night. I ate a small bag of chips & it's back again! So, am I pregnant? Or just bloated due to constipation & stress is causing the lack of period? I have been suuuuuuper stressed lately.