Brief Answer:
You can find ovulation kits otc in pharmacy.

Detailed Answer:
Hello dear, welcome to Ask a doctor service.
I read your query and here is my advice.

Having irregular periods makes finding ovulation a bit difficult.
1.You have to write in calendar the first day of cycle in order to know the first day of last period when asked later.
2. Measures the body temperature every day in mornings. An increase with half a degree of body temperature shows ovulation.
3. Track vaginal mucus changes. Fist days it is dry but near ovulation it becomes white, transparent with loose consistency as egg whites.
4. You can find in pharmacy over the counter ovulation tracking kits that resample those of pregnancy tests. They track ovulation and are highly reliable.

Hope I have answered the question.
Let me know if I can assist you further.

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