Could I be pregnant?

Ok so I was 5 days late for my period but I started it on February 26. It lasted a good 4-5 days. We have been TTC for like 7-8 months. My boobs have been very sensitive and kind of achy to the touch lately and I’ve been super tired. I didn’t think much of it u til my younger sister (3 years younger than me) just announced that she was unexpectedly pregnant. Now I’m kind of sad and slightly jealous because I wanted that to be me. Now I’m kind of wondering if I could still be pregnant and my phone says I’m due in 5-6 days for my next period.