I am new to soldering, and I am not sure if I did a good job while trying to solder some pins into a HX711. My concern is that the solder in SCK and VCC are touching (also E+ and E-), so I thought this might create some electrical noise, leading to mis-measurements.
It could certainly serve as a bad example.
Heat applied to the wrong place, no flux, some combination of those. Fortunately there are plenty of videos showing the right way to do it.
As long as you start with a nicely tinned soldering iron tip at some reasonable temperature and use good flux-core solder on fresh boards and parts you should never see anything like this.
I'm guessing how this solder-job went wrong...
Since the pad received no heat, it didn't attract any solder. Both pin and pad must be heated by the soldering iron tip at the same time. After heating for a second-or-two, push solder into the area between pin and pad...rather than pushing solder into the soldering-iron-tip.
Solder containing flux should wick nicely into the space between pin and pad. Then pull the tip away from the joint.
No, I wouldn't approve the job. The grey frosted look of the two solders near your thumb are a pretty clear indication of a cold solder joint. That could fail unpredictably, and Murphy's Law says at the worst possible moment.
The B+ node looks like it might be shorted to the B- node. In general, there's too much solder at each joint, to the point where shorts are likely. It also doesn't look like the plating on the through holes was heated at all.
As a rule, heat the joint, not the solder, and then touch the solder to a part of the joint you believe is hot, and not the iron tip. If the solder melts, you're closer to doing it correctly than you are now.
No, those joints are not ok in their current form.
However it is likely easier to complete the remainder of the joints before going back and cleaning up the bad ones, getting a good solder joint while at the same time trying to stop a part falling out is much harder than doing the two jobs seperately.
There is not a single solder point on that image that isn't plain ridiculous, with far too much solder but none actually flowing on any solder pad. You say "I am not sure if I did a good job". That is really hard to believe since comparing with any circuit board should tell you how a sane solder joint looks, not with a ball of solder hanging in the air but with a (usually slightly concave) cone of solder covering the solder pad at its base and climbing up due to cohesion on the wire which forms an alloy at its surface with the solder, like the solder pad does.
Insufficient heating of the contact points leads to "cold" solder joints missing that alloying and not having reliable contact. They can be hard to see when they are not as strikingly bad as on your picture. So you may want to have someone help/teach you before improving your technique from producing obviously bad joints to hard to see bad joints.
