Posted: 12/06/2016 at 13:05
I agree with others, that with those symptoms, you HAVE to go see your GP.
However, if the GP is happy you're okay, then it probably is just a question of slowing down even more on the runs or running for shorter periods.
I know you say you can walk almost as fast, but running is a different action and is more tiring than walking even at the same pace. If you can't carry out a conversation whilst running (even a breathless, slightly incoherent one counts) and you are exhausted afterwards, then you are clearly working harder than you think
You say you are a little overweight. As someone who is more than a little overweight, don't underestimate the effect that can have on your ability to run. However overweight you are, imagine that weight on your back in a rucksack (this is what I am currently repeatedly telling myself and every little bit off is going to help!).
And if it is just overweight/ lack of fitness, then the good news is it will get better. Just stick at it.
But please see your GP and get it confirmed that that is all it is.