Aww mama, 17 years is such a long journey, my heart goes out to you! A few of us in our mum circle have used ovulation kits, and honestly, they do help you pinpoint your fertile window, though results can vary, some of us got our positives after consistent tracking, pero kailangan din ng patience at timing. Have you tried the digital ones? Parang Clearblue, mas clear ang results compared sa the line-reading kits na sometimes confusing talaga. Sending you so much hope, at don't hesitate to check with your OB too if you haven't yet, they can give you a more personalized plan based on your situation. Rooting for you!