Not really. They identify the virus in your system (and normal vaccines typically use a "dead" or otherwise mostly disabled virus for this), map it out, and create T-cells or whatever that will go after it. What mRNA does is not expose your system to the virus at all. What it does is present the blueprints to actually manufacture part of the virus (in this case, the spike protein), which then your body identifies, and creates T-cells, and destroys. Problem is, there are thousands of cases where after shot 2 the person suddenly died of cardiac or other organ failure, or developed an autoimmune disorder, etc. Why? Presumably, the body the second time around identified whatever organ that got involved in manufacturing the spikes by the mRNA as the source of the spike proteins, and attacked it not just the spike proteins. Results not pretty.
Other issues have involved horrific looking blood clots clogging up stuff and killing people that way. One theory where they come from is too many spike proteins are manufactured (some doses of the shots were stronger, had more mRNA in it, etc - they were not all the same), and they would end up essentially damage stuff like little blades soaring through your system and collect tons of platelets or whatever else that was trying to fix it up and create nasty clots.
There's other thoughts on this stuff too by smarter people than me. Dr Malone is a pioneer in mRNA and can tell you all about the problems with its use.
It very well may have been the reason that you had only a mild case. Entirely possible. But I know of people who got COVID and had similar mild symptoms, and they weren't vaccinated at all. I wouldn't quickly attribute your vaccine for that.