Tyre detached from wheel

[rliu]

I don't know how this had occurred and only realised after trying to ride an old second hand mountain bike that the tyre had become detached from the wheel. At the moment the tyre is flat and I can't pump it up. I don't know quite how to describe it but the tyre has become detached from the edges of the wheel. What should I do in this situation? I could upload photos if that would help you in giving an answer

 

[asterix]

Yes, show us the full horror!

 

[exbfb]

A simple puncture to the inner tube by the sounds of it.
If you have never done this before, it's relatively simple and you will find guides shwoing you how to fix it.

Once you have the inner tube repaired, you will be up and running again in no time at all.

 

[rliu]

Update - I've replaced the inner tube but now the wheel keeps tilting to the left upon riding. The wheel itself is straight so do you think the cause of this tilting could be because the nuts securing the wheel are old and aren't secure any more?

 

[Mad at urage]

Or it isn't fully home in the drop-outs

Or the nuts just haven't been tightened sufficiently

 

[Angelfishsolo]

+1 - A photo would help a lot here.

Or it isn't fully home in the drop-outs

Or the nuts just haven't been tightened sufficiently

 

[BigTone0777]

Is it the rear wheel? If so there might not be enough spacers on the axle meaning that when you apply pressure to the pedals it is moving the wheel in the dropouts. The axle locknuts should be spaced so that they touch the inside of the dropouts without any pressure on them which will secure the wheel correctly.