Since the others seem to have run out of patience to answer your questions, I will give you the benefit of the doubt and provide you with some information. However, because you are asking such basic questions about laser safety, I would recommend that you do some research to protect yourself - there is a large wealth of information on this forum accessible with a simple search. After all, your eyes do not heal from optical damage. Once the damage is done, it is permanent. Please treat and use lasers with respect.
First, looking at the *dot* of a >500mW laser can cause permanent damage to your eyes. This is called diffuse reflection (a laser bouncing off of a mirror or other reflective surface would be called a spectral reflection - for a direct/reflected hit into your eyes, anything >5mW can cause permanent damage). The reason you see a laser beam in midair is not caused by this same phenomenon - it is due to Rayleigh scattering (or particulates in the air in the case of dense fog or dust - think nightclubs). Assuming you are not using your laser in a densely particulate area, at the range of watts, looking at a laser beam (that is not directed towards you) will not hurt your eyes. It is also not strong enough to vaporize/"cut" metal. Something more like 100W properly focused would be able to. Thus, in theory, it is safe to shine a 7 watt blue laser into the sky without laser goggles on. However, if a bug happens to fly into that beam... now you've inadvertently looked at the laser's dot, so that bug may have just given you permanent eye damage. It has happened before.
Since you are primarily dealing with a high-powered blue laser, if you notice that your vision is yellow-tinged after using your blue laser, it is possible that you have damaged your eyes with blue laser light. For a green laser, a red tinge would be your warning call. A direct shot into your eyes with a >500mW laser is likely to cause immediate blindness, or at least, a hole in your vision, immediately. This is a medical emergency, as the resulting inflammation from the vaporized spot on your retina may cause the retina to detach off of the eye, resulting in total blindness and pressure/fluid buildup behind the eye, which can lead to a whole slew of other complications. While we are on the subject, I will add that laser goggles are meant to protect you from an *accidental* exposure to the direct laser beam. This means that if you deliberately look directly into the laser with your goggles on, you will still end up blinded. Why? Because the laser melted through your goggles and went into your eyes. Please be careful. Hope this helps