You wrote, " constraining me to staying inside the house since it all started." We would say "forcing me to remain (OR to stay) inside the house since it all started." FORCING is a present participle that goes with SYMPTOMS. FORCING takes an infinitive after it. Let me rewrite what I think you are trying to say: These symptoms have gotten worse (OR have worsened) over the last several weeks, even though I only do mild exercise for a few minutes at a time, forcing me to stay inside the house since it all started. Because of this, researching and writing about crypto (What is crypto?) for a few hours a day is the only thing (that) I can do. My participle is dangling :( Would someone else like to suggest another way of writing this?

"constraining me to staying....what the purpose of using the two verps in progress(v ing)" The present progressive form "constraining" is used as the action (being constrained) is ongoing and still in progress. The same applies for "staying". Constraining is an odd word to use here in my opinion. I think "restricting" would've been a better choice.

Those symptoms worsen for weeks and months with only mild exercise for a few minutes, constraining me to staying inside the house since it all started. Researching and writing about crypto a few hours a day is pretty much the only thing I can do for that reason "constraining me to staying" constraining (present participle) staying (gerund) The author is using "to constrain to <gerund>" probably in analogy to "to limit to <gerund>." The New Oxford American Dictionary gives "to constrain to <infinitive>." constrain | kənˈstreɪn | verb [with object] compel or force (someone) toward a particular course of action: children are constrained to work in the way the book dictates.

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