Understanding and promoting researchers' well-being is crucial for successful research outcomes and a thriving scientific community. Traditional well-being assessments can be resource-intensive, prompting the computational analysis of academic social networks as a promising alternative. It has been shown that sentiment analysis of social media text data can be used to infer well-being in the general population, but it is not known whether this approach is transferable to the specific subgroup of researchers. This proof-of-concept study addresses this research question by assessing the potential of scholarly communication in social media to provide insights into researchers' emotional well-being using sentiment analysis. Therefore, we derived researchers’ emotional well-being from a dataset of more than 13 Million tweets from almost 16,000 psychology researchers, and utilized survey data from the COVID-19 pandemic for external validation of our results. Our aim was to confirm two hypotheses: lower well-being during the pandemic (H1) and a stronger impact on female researchers (H2). Using structural break analysis, the impact of the pandemic was found to be statistically significant for positive sentiments. A differential effect by gender was observed descriptively, but did not reach statistical significance. Results suggest that sentiment analysis of researchers’ tweets can provide insights into their well-being, but to a limited extent than in the general population. Exploratory analysis of cognitive well-being revealed that some, but not all PERMA+4 dimensions are prevalent in researchers' social media posts. We discuss promising expansions of our approach and highlight practical implications for policymakers.