When am I ovulating?

Glow says 3 days.

I’ve had thick goeey white discharge, from time to time I go extremely pale and dizzy and literally nearly pass out. This has happened about 2-3 times the last few days. It is really hot in the UK so I’m thinking it could be heat also but when would the best time be to start having sex? I know the apps aren’t 100% accurate as it just goes by what information you put in. Just a little friendly advice or tips may help. 😘