When should i notice a difference in my fitness?

i am a 22 yr old. my fitness is absolutely shocking. i start running and in minutes im out of breath. i started the gym 3 days ago and have been every morning for about 30 mins. Its a bit embarrassing when i have to keep stopping to gasp for air. how long will it take until i can see a difference in my fitness?When should i notice a difference in my fitness?You should notice an improvement in endurance fairly quickly but it usually takes about 6 weeks to really see any improvement from a regular exercise regimen.