Feeling defeated

I recently started getting back into loosing weight after having my baby and was going about 6 days a week for 2 weeks straight and then 4th of July weekend hit and my gym was closed for 4 days and I lost 4 days of working out and the holiday I was spending with my family

I finally came back to the gym once they opened and I lost all the stamina I had and I feel so defeated and like I took a step back and lost all my progress and I’m back to square one..