I do not think you are pregnant. The reasons are;
1) Condom was used which has high protection rate.
2) Your symptoms do not suggest pregnancy. These symptoms also occur when period is due because of hormonal changes in the body. Anxiety can also cause these symptoms.
3) Period can delay because of many reasons, apart from pregnancy, especially when you mentioned that your periods are irregular. Just anxiety can delay the period.
So please do not worry.
Apart from pregnancy there are other causes of missed or delayed periods;
1) Ovarian hormone dysfunctions
2) Thyroid hormone abnormalities
3) Stress, anxiety, emotional disorders
4) Sudden weight loss or gain
5) Excessive physical activity
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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