Going back to work can be pretty traumatic. Well done on getting through your first day.
Technically, 4.4 is not a hypo. However, I can imagine it felt nasty. As you bring you BG down and you get used to "normal" levels, you should not get any symptoms until you are under 4.0.
If your BG is falling too much, you (with help from you diabetes team) need the look at why this is happening. It is likely to be too much insulin. If you didn't snack mid morning before you had diabetes, you should be able to do the same now.
Regarding your eye sight, this should go back to normal. When our BG is too high, our body tries to get rid of the extra sugar in all sorts of ways... wee, sweat, saliva (some people are diagnosed after a visit to the dentist) and tears (mine tasted sweet rather than salty). The problem with sugary tears is they have a different density to salty tears which affects the focal length. Until this gets back to normal, it is not advised to change glasses or contact lenses. Give it time ...