Assalamu alaykum Ahsanallahu ilaykum I may have some fasts that I have to make up for. But I’m not 100% if I really some days to make up. What should I do in this case ? From the time when I was 13-15 years old but still not really sure. Is this maybe waswas?

Ustadh AbdulAziz al-Haqqan
If you suffer from waswas then it could very much be waswas may Allah protect u so u can ignore it, if this is the case keep in mind.