Two steps forward...one step back

I'm at the end of day 3 potty training following big little feelings (day 1 naked from waist down, day 2 with baggy trousers and day 3 short outings). My LG is 28 months and did really well on day 1 and 2. She managed a short outing this morning and wee'd on the potty when we got in but after that it's been 100% accidents and she is now pretending not to hear us whenever we mention potty or needing a wee / poo. Anyone had anything similar and got any tips? I'm tearing my hair out because she was doing so well! I don't know whether to give up and try again in a few weeks or persevere