How accurate is this app? Should I get my hopes up?

So I’m 10 months PP, still breastfeeding and have had irregular periods since having my son. I tracked my ovulation after my most recent period (27th June-1st July). The tests said I was ovulating on the 23rd of July. I’ve had no period or any sign of a period since. I’ve been sooo nauseous for 4 days now, which has gotten worse yesterday and today. I’ve took a test everyday for a week but they all look negative to me. However this app seems to think differently? What do yous think? Yesterday’s test pic…