Can the pill make you feel sick?

I’m not asking for myself, I’m asking for my friend (who doesn’t want to make an <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> account 😂🙄) anyways yeah but my friend got diagnosed with endometriosis and her dr put her on the pill. She started taking them 2 weeks ago and ever since she started taking them she’s been feeling unwell. She says she’s bloated 24/7, she’s tired, and nauseous. Is it the pill making her feel like this? Or the endometriosis? Like should she go back to the dr?