[Chinmay]

have you tried a loft between the circular sketch and a sketch on the end of your tube? depending on how you want to do this, you can either make the "midair circle" 2 concentric midair circles with the desired thickness of the shell, or you can loft the part and then shell the feature you created. hint: the first way is easier.

alternate methods: you can draw the profile from the side view and revolve it around an axis through the center of your tube.
you can extrude the circle you currently and choose to extrude it at an angle... solidworks has an option called taper or something and im sure inventor has a similar feature. Basically, there are several ways, but the first will probably be the easiest.

good luck, and if this doesnt work, reply and ill be more specific